{
    "document": {
        "category": "csaf_base",
        "csaf_version": "2.0",
        "distribution": {
            "tlp": {
                "label": "WHITE"
            }
        },
        "lang": "en",
        "notes": [
            {
                "category": "legal_disclaimer",
                "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
            }
        ],
        "publisher": {
            "category": "coordinator",
            "contact_details": "cert@ncsc.nl",
            "name": "National Cyber Security Centre",
            "namespace": "https://www.ncsc.nl/"
        },
        "title": "CVE-2026-33248",
        "tracking": {
            "current_release_date": "2026-03-29T01:16:18.698125Z",
            "generator": {
                "date": "2026-02-17T15:00:00Z",
                "engine": {
                    "name": "V.E.L.M.A",
                    "version": "1.7"
                }
            },
            "id": "CVE-2026-33248",
            "initial_release_date": "2026-03-24T23:11:51.878430Z",
            "revision_history": [
                {
                    "date": "2026-03-24T23:11:51.878430Z",
                    "number": "1",
                    "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (3).| CWES updated (1)."
                },
                {
                    "date": "2026-03-24T23:12:02.335490Z",
                    "number": "2",
                    "summary": "NCSC Score created."
                },
                {
                    "date": "2026-03-25T11:35:54.608947Z",
                    "number": "3",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-25T13:15:16.097386Z",
                    "number": "4",
                    "summary": "Source connected.| CVE status created. (valid)| Products connected (2).| References created (13)."
                },
                {
                    "date": "2026-03-25T13:15:24.579163Z",
                    "number": "5",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-25T18:12:50.368705Z",
                    "number": "6",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (2).| References created (2).| CWES updated (1)."
                },
                {
                    "date": "2026-03-25T20:38:44.838097Z",
                    "number": "7",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (2).| References created (2).| CWES updated (1)."
                },
                {
                    "date": "2026-03-25T20:38:52.841974Z",
                    "number": "8",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-25T21:32:01.098254Z",
                    "number": "9",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)."
                },
                {
                    "date": "2026-03-25T21:32:03.171870Z",
                    "number": "10",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-26T00:27:52.442409Z",
                    "number": "11",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (4).| Product Identifiers created (2).| Product Remediations created (4).| References created (4).| CWES updated (1).| Vendor_assessment created."
                },
                {
                    "date": "2026-03-26T00:28:04.158949Z",
                    "number": "12",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-26T12:44:28.721746Z",
                    "number": "13",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| Products connected (1)."
                },
                {
                    "date": "2026-03-26T15:02:13.449723Z",
                    "number": "14",
                    "summary": "Source connected.| CVE status created. (valid)| EPSS created."
                },
                {
                    "date": "2026-03-26T15:02:16.086777Z",
                    "number": "15",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-26T16:26:34.674296Z",
                    "number": "16",
                    "summary": "Products created (2).| Product Identifiers created (2)."
                },
                {
                    "date": "2026-03-26T16:26:40.686389Z",
                    "number": "17",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-26T20:39:27.384113Z",
                    "number": "18",
                    "summary": "Unknown change."
                },
                {
                    "date": "2026-03-26T20:39:30.791854Z",
                    "number": "19",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-26T23:43:48.895025Z",
                    "number": "20",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-27T00:13:44.069755Z",
                    "number": "21",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| References created (2)."
                },
                {
                    "date": "2026-03-28T07:57:39.461619Z",
                    "number": "22",
                    "summary": "References created (1)."
                },
                {
                    "date": "2026-03-28T07:57:52.530918Z",
                    "number": "23",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-03-28T08:10:32.956691Z",
                    "number": "24",
                    "summary": "References removed (1)."
                },
                {
                    "date": "2026-03-29T01:16:08.814504Z",
                    "number": "25",
                    "summary": "References created (1)."
                }
            ],
            "status": "interim",
            "version": "25"
        }
    },
    "product_tree": {
        "branches": [
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:rpm/unknown",
                                "product": {
                                    "name": "vers:rpm/unknown",
                                    "product_id": "CSAFPID-2552008",
                                    "product_identification_helper": {
                                        "cpe": "cpe:/a:redhat:multicluster_globalhub"
                                    }
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "Multicluster Global Hub"
                    },
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:rpm/4",
                                "product": {
                                    "name": "vers:rpm/4",
                                    "product_id": "CSAFPID-1439328",
                                    "product_identification_helper": {
                                        "cpe": "cpe:/a:redhat:openshift:4"
                                    }
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "Red Hat OpenShift Container Platform 4"
                    },
                    {
                        "branches": [
                            {
                                "branches": [
                                    {
                                        "category": "product_version_range",
                                        "name": "vers:rpm/unknown",
                                        "product": {
                                            "name": "vers:rpm/unknown",
                                            "product_id": "CSAFPID-2914734"
                                        }
                                    }
                                ],
                                "category": "product_name",
                                "name": "multicluster-globalhub-grafana-rhel9"
                            }
                        ],
                        "category": "product_family",
                        "name": "Multicluster Global Hub"
                    },
                    {
                        "branches": [
                            {
                                "branches": [
                                    {
                                        "category": "product_version_range",
                                        "name": "vers:rpm/unknown",
                                        "product": {
                                            "name": "vers:rpm/unknown",
                                            "product_id": "CSAFPID-2257522"
                                        }
                                    }
                                ],
                                "category": "product_name",
                                "name": "oc-mirror-plugin-rhel9"
                            }
                        ],
                        "category": "product_family",
                        "name": "Red Hat OpenShift Container Platform 4"
                    }
                ],
                "category": "vendor",
                "name": "Red Hat"
            },
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/<2.11.15",
                                "product": {
                                    "name": "vers:unknown/<2.11.15",
                                    "product_id": "CSAFPID-5906252"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/<2.12.6",
                                "product": {
                                    "name": "vers:unknown/<2.12.6",
                                    "product_id": "CSAFPID-5906253"
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "NATS Server"
                    }
                ],
                "category": "vendor",
                "name": "Open Source"
            },
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/<2.11.15",
                                "product": {
                                    "name": "vers:unknown/<2.11.15",
                                    "product_id": "CSAFPID-5903111"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/>=0|<2.11.15",
                                "product": {
                                    "name": "vers:unknown/>=0|<2.11.15",
                                    "product_id": "CSAFPID-5907189"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/>=2.12.0-rc.1|<2.12.6",
                                "product": {
                                    "name": "vers:unknown/>=2.12.0-rc.1|<2.12.6",
                                    "product_id": "CSAFPID-5903112"
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "Nats Server"
                    }
                ],
                "category": "vendor",
                "name": "Nats"
            },
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "branches": [
                                    {
                                        "category": "product_version_range",
                                        "name": "vers:deb/unknown",
                                        "product": {
                                            "name": "vers:deb/unknown",
                                            "product_id": "CSAFPID-2649998"
                                        }
                                    }
                                ],
                                "category": "product_name",
                                "name": "nats-server"
                            }
                        ],
                        "category": "product_family",
                        "name": "bookworm"
                    }
                ],
                "category": "vendor",
                "name": "Debian"
            },
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/<2.11.15",
                                "product": {
                                    "name": "vers:unknown/<2.11.15",
                                    "product_id": "CSAFPID-5918227",
                                    "product_identification_helper": {
                                        "cpe": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*"
                                    }
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/>=2.12.0|<2.12.6",
                                "product": {
                                    "name": "vers:unknown/>=2.12.0|<2.12.6",
                                    "product_id": "CSAFPID-5918228",
                                    "product_identification_helper": {
                                        "cpe": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*"
                                    }
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "nats-server"
                    }
                ],
                "category": "vendor",
                "name": "linuxfoundation"
            }
        ]
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-33248",
            "cwe": {
                "id": "CWE-295",
                "name": "Improper Certificate Validation"
            },
            "notes": [
                {
                    "category": "description",
                    "text": "### Background\n\nNATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.\n\nOne authentication model supported is mTLS, deriving the NATS client identity from properties of the TLS Client Certificate.\n\n### Problem Description\n\nWhen using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass.\n\nThis does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely.\n\nSo this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted.\n\n### Affected Versions\n\nFixed in nats-server 2.12.6 & 2.11.15\n\n### Workarounds\n\nDevelopers should review their CA issuing practices.",
                    "title": "github - https://api.github.com/advisories/GHSA-3f24-pcvm-5jqc"
                },
                {
                    "category": "description",
                    "text": "### Background\n\nNATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.\n\nOne authentication model supported is mTLS, deriving the NATS client identity from properties of the TLS Client Certificate.\n\n### Problem Description\n\nWhen using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass.\n\nThis does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely.\n\nSo this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted.\n\n### Affected Versions\n\nFixed in nats-server 2.12.6 & 2.11.15\n\n### Workarounds\n\nDevelopers should review their CA issuing practices.",
                    "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGHSA-3f24-pcvm-5jqc.json?alt=media"
                },
                {
                    "category": "description",
                    "text": "NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, when using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass. This does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely. So this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, developers should review their CA issuing practices.",
                    "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33248.json"
                },
                {
                    "category": "description",
                    "text": "NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, when using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass. This does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely. So this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, developers should review their CA issuing practices.",
                    "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33248"
                },
                {
                    "category": "description",
                    "text": "A flaw was found in NATS-Server, a high-performance messaging system. When configured to use mutual Transport Layer Security (mTLS) for client identity, and specifically the `verify_and_map` feature, certain patterns within a client certificate's Subject Distinguished Name (DN) were not correctly enforced. This could allow an attacker, possessing a valid certificate from a trusted Certificate Authority (CA), to bypass the intended identity verification. Consequently, this could lead to unauthorized access, although the attack requires highly specific and unlikely DN naming patterns.",
                    "title": "redhat - https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33248.json"
                },
                {
                    "category": "description",
                    "text": "NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, when using mTLS for client identity, with `verify_and_map` to derive a NATS identity from the client certificate's Subject DN, certain patterns of RDN would not be correctly enforced, allowing for authentication bypass. This does require a valid certificate from a CA already trusted for client certificates, and `DN` naming patterns which the NATS maintainers consider highly unlikely. So this is an unlikely attack. Nonetheless, administrators who have been very sophisticated in their `DN` construction patterns might conceivably be impacted. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, developers should review their CA issuing practices.",
                    "title": "debian - https://security-tracker.debian.org/tracker/CVE-2026-33248"
                },
                {
                    "category": "description",
                    "text": "NATS has mTLS verify_and_map authentication bypass via incorrect Subject DN matching in github.com/nats-io/nats-server",
                    "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGO-2026-4828.json?alt=media"
                },
                {
                    "category": "other",
                    "text": "0.0002",
                    "title": "EPSS"
                },
                {
                    "category": "other",
                    "text": "4.2",
                    "title": "NCSC Score"
                },
                {
                    "category": "other",
                    "text": "There is product data available from source Certbundde",
                    "title": "NCSC Score top increasing factors"
                },
                {
                    "category": "other",
                    "text": "There is product data available from source Debian, The value of the most recent CVSS (V3) score, The value of the most recent EPSS score, Is related to (a version of) an uncommon product, Is related to an uncommon product vendor",
                    "title": "NCSC Score top decreasing factors"
                },
                {
                    "category": "details",
                    "text": "Severity: 2\n",
                    "title": "Vendor assessment"
                }
            ],
            "product_status": {
                "known_affected": [
                    "CSAFPID-5906252",
                    "CSAFPID-5906253",
                    "CSAFPID-5903112",
                    "CSAFPID-5907189",
                    "CSAFPID-5903111",
                    "CSAFPID-1439328",
                    "CSAFPID-2257522",
                    "CSAFPID-2552008",
                    "CSAFPID-2914734",
                    "CSAFPID-2649998",
                    "CSAFPID-5918227",
                    "CSAFPID-5918228"
                ]
            },
            "references": [
                {
                    "category": "external",
                    "summary": "Source - github",
                    "url": "https://api.github.com/advisories/GHSA-3f24-pcvm-5jqc"
                },
                {
                    "category": "external",
                    "summary": "Source - certbundde",
                    "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0858.json"
                },
                {
                    "category": "external",
                    "summary": "Source - osv",
                    "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGHSA-3f24-pcvm-5jqc.json?alt=media"
                },
                {
                    "category": "external",
                    "summary": "Source - cveprojectv5",
                    "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33248.json"
                },
                {
                    "category": "external",
                    "summary": "Source - nvd",
                    "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33248"
                },
                {
                    "category": "external",
                    "summary": "Source - redhat",
                    "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33248.json"
                },
                {
                    "category": "external",
                    "summary": "Source - debian",
                    "url": "https://security-tracker.debian.org/tracker/CVE-2026-33248"
                },
                {
                    "category": "external",
                    "summary": "Source - first",
                    "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0"
                },
                {
                    "category": "external",
                    "summary": "Source - osv",
                    "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGO-2026-4828.json?alt=media"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd; osv; redhat",
                    "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-3f24-pcvm-5jqc"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde; cveprojectv5; github; nvd; osv; redhat",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-13.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/advisories/GHSA-3f24-pcvm-5jqc"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0858.json"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-0858"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-05.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-06.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-07.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-08.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-09.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-10.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-11.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-12.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-14.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - certbundde",
                    "url": "https://advisories.nats.io/CVE/secnote-2026-15.txt"
                },
                {
                    "category": "external",
                    "summary": "Reference - redhat",
                    "url": "https://www.cve.org/CVERecord?id=CVE-2026-33248"
                },
                {
                    "category": "external",
                    "summary": "Reference - github; redhat",
                    "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33248"
                }
            ],
            "remediations": [
                {
                    "category": "mitigation",
                    "details": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.",
                    "product_ids": [
                        "CSAFPID-1439328",
                        "CSAFPID-2257522",
                        "CSAFPID-2552008",
                        "CSAFPID-2914734"
                    ]
                }
            ],
            "scores": [
                {
                    "cvss_v3": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
                        "baseScore": 4.8,
                        "baseSeverity": "MEDIUM"
                    },
                    "products": [
                        "CSAFPID-1439328",
                        "CSAFPID-2257522",
                        "CSAFPID-2552008",
                        "CSAFPID-2649998",
                        "CSAFPID-2914734",
                        "CSAFPID-5903111",
                        "CSAFPID-5903112",
                        "CSAFPID-5906252",
                        "CSAFPID-5906253",
                        "CSAFPID-5907189",
                        "CSAFPID-5918227",
                        "CSAFPID-5918228"
                    ]
                }
            ],
            "title": "CVE-2026-33248"
        }
    ]
}