{
    "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-2026-34785",
        "tracking": {
            "current_release_date": "2026-04-03T15:37:56.331310Z",
            "generator": {
                "date": "2026-02-17T15:00:00Z",
                "engine": {
                    "name": "V.E.L.M.A",
                    "version": "1.7"
                }
            },
            "id": "CVE-2026-34785",
            "initial_release_date": "2026-04-02T17:28:25.856317Z",
            "revision_history": [
                {
                    "date": "2026-04-02T17:28:25.856317Z",
                    "number": "1",
                    "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (1).| CWES updated (1)."
                },
                {
                    "date": "2026-04-02T17:28:29.558712Z",
                    "number": "2",
                    "summary": "NCSC Score created."
                },
                {
                    "date": "2026-04-02T17:39:36.040737Z",
                    "number": "3",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (3).| References created (1).| CWES updated (1)."
                },
                {
                    "date": "2026-04-02T17:39:37.851911Z",
                    "number": "4",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-04-02T19:39:46.568759Z",
                    "number": "5",
                    "summary": "Unknown change."
                },
                {
                    "date": "2026-04-02T20:12:02.055162Z",
                    "number": "6",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (3).| CWES updated (1)."
                },
                {
                    "date": "2026-04-03T00:44:15.977468Z",
                    "number": "7",
                    "summary": "Source created.| CVE status created. (valid)| Products connected (2)."
                },
                {
                    "date": "2026-04-03T06:45:59.410334Z",
                    "number": "8",
                    "summary": "Description created for source."
                },
                {
                    "date": "2026-04-03T15:30:59.263467Z",
                    "number": "9",
                    "summary": "Source connected.| CVE status created. (valid)| EPSS created."
                },
                {
                    "date": "2026-04-03T15:31:02.276883Z",
                    "number": "10",
                    "summary": "NCSC Score updated."
                }
            ],
            "status": "interim",
            "version": "10"
        }
    },
    "product_tree": {
        "branches": [
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/<2.2.23",
                                "product": {
                                    "name": "vers:unknown/<2.2.23",
                                    "product_id": "CSAFPID-5985093"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/>=3.0.0.beta1|<3.1.21",
                                "product": {
                                    "name": "vers:unknown/>=3.0.0.beta1|<3.1.21",
                                    "product_id": "CSAFPID-5985094"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/>=3.2.0|<3.2.6",
                                "product": {
                                    "name": "vers:unknown/>=3.2.0|<3.2.6",
                                    "product_id": "CSAFPID-5985095"
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "rack"
                    }
                ],
                "category": "vendor",
                "name": "rack"
            },
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "branches": [
                                    {
                                        "category": "product_version_range",
                                        "name": "vers:deb/unknown",
                                        "product": {
                                            "name": "vers:deb/unknown",
                                            "product_id": "CSAFPID-2065710"
                                        }
                                    }
                                ],
                                "category": "product_name",
                                "name": "ruby-rack"
                            }
                        ],
                        "category": "product_family",
                        "name": "bookworm"
                    },
                    {
                        "branches": [
                            {
                                "branches": [
                                    {
                                        "category": "product_version_range",
                                        "name": "vers:deb/unknown",
                                        "product": {
                                            "name": "vers:deb/unknown",
                                            "product_id": "CSAFPID-2065711"
                                        }
                                    }
                                ],
                                "category": "product_name",
                                "name": "ruby-rack"
                            }
                        ],
                        "category": "product_family",
                        "name": "bullseye"
                    }
                ],
                "category": "vendor",
                "name": "Debian"
            }
        ]
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-34785",
            "cwe": {
                "id": "CWE-187",
                "name": "Partial String Comparison"
            },
            "notes": [
                {
                    "category": "description",
                    "text": "Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as \"/css\", it matches any request path that begins with that string, including unrelated paths such as \"/css-config.env\" or \"/css-backup.sql\". As a result, files under the static root whose names merely share the configured prefix may be served unintentionally, leading to information disclosure. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.",
                    "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34785"
                },
                {
                    "category": "description",
                    "text": "Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as \"/css\", it matches any request path that begins with that string, including unrelated paths such as \"/css-config.env\" or \"/css-backup.sql\". As a result, files under the static root whose names merely share the configured prefix may be served unintentionally, leading to information disclosure. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.",
                    "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34785.json"
                },
                {
                    "category": "description",
                    "text": "## Summary\n\n`Rack::Static` determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as `\"/css\"`, it matches any request path that begins with that string, including unrelated paths such as `\"/css-config.env\"` or `\"/css-backup.sql\"`.\n\nAs a result, files under the static root whose names merely share the configured prefix may be served unintentionally, leading to information disclosure.\n\n## Details\n\n`Rack::Static#route_file` performs static-route matching using logic equivalent to:\n\n```ruby\n@urls.any? { |url| path.index(url) == 0 }\n```\n\nThis checks only whether the request path starts with the configured prefix string. It does not require a path segment boundary after the prefix.\n\nFor example, with:\n\n```ruby\nuse Rack::Static, urls: [\"/css\", \"/js\"], root: \"public\"\n```\n\nthe following path is matched as intended:\n\n```text\n/css/style.css\n```\n\nbut these paths are also matched:\n\n```text\n/css-config.env\n/css-backup.sql\n/csssecrets.yml\n```\n\nIf such files exist under the configured static root, Rack forwards the request to the file server and serves them as static content.\n\nThis means a configuration intended to expose only directory trees such as `/css/...` and `/js/...` may also expose sibling files whose names begin with those same strings.\n\n## Impact\n\nAn attacker can request files under the configured static root whose names share a configured URL prefix and obtain their contents.\n\nIn affected deployments, this may expose configuration files, secrets, backups, environment files, or other unintended static content located under the same root directory.\n\n## Mitigation\n\n* Update to a patched version of Rack that enforces a path boundary when matching configured static URL prefixes.\n* Match only paths that are either exactly equal to the configured prefix or begin with `prefix + \"/\"`.\n* Avoid placing sensitive files under the `Rack::Static` root directory.\n* Prefer static URL mappings that cannot overlap with sensitive filenames.",
                    "title": "github - https://api.github.com/advisories/GHSA-h2jq-g4cq-5ppq"
                },
                {
                    "category": "description",
                    "text": "Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as \"/css\", it matches any request path that begins with that string, including unrelated paths such as \"/css-config.env\" or \"/css-backup.sql\". As a result, files under the static root whose names merely share the configured prefix may be served unintentionally, leading to information disclosure. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.",
                    "title": "debian - https://security-tracker.debian.org/tracker/CVE-2026-34785"
                },
                {
                    "category": "other",
                    "text": "0.00031",
                    "title": "EPSS"
                },
                {
                    "category": "other",
                    "text": "4.2",
                    "title": "NCSC Score"
                },
                {
                    "category": "other",
                    "text": "The value of the most recent EPSS score, Is related to (a version of) an uncommon product, There is cwe data available from source Nvd",
                    "title": "NCSC Score top decreasing factors"
                }
            ],
            "product_status": {
                "known_affected": [
                    "CSAFPID-5985093",
                    "CSAFPID-5985094",
                    "CSAFPID-5985095",
                    "CSAFPID-2065710",
                    "CSAFPID-2065711"
                ]
            },
            "references": [
                {
                    "category": "external",
                    "summary": "Source - nvd",
                    "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34785"
                },
                {
                    "category": "external",
                    "summary": "Source - cveprojectv5",
                    "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34785.json"
                },
                {
                    "category": "external",
                    "summary": "Source - github",
                    "url": "https://api.github.com/advisories/GHSA-h2jq-g4cq-5ppq"
                },
                {
                    "category": "external",
                    "summary": "Source - debian",
                    "url": "https://security-tracker.debian.org/tracker/CVE-2026-34785"
                },
                {
                    "category": "external",
                    "summary": "Source - first",
                    "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd",
                    "url": "https://github.com/rack/rack/security/advisories/GHSA-h2jq-g4cq-5ppq"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34785"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/advisories/GHSA-h2jq-g4cq-5ppq"
                }
            ],
            "scores": [
                {
                    "cvss_v3": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH"
                    },
                    "products": [
                        "CSAFPID-2065710",
                        "CSAFPID-2065711",
                        "CSAFPID-5985093",
                        "CSAFPID-5985094",
                        "CSAFPID-5985095"
                    ]
                }
            ],
            "title": "CVE-2026-34785"
        }
    ]
}