{ "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-2026-33898", "tracking": { "current_release_date": "2026-04-01T18:27:52.591743Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-33898", "initial_release_date": "2026-03-26T23:38:49.127865Z", "revision_history": [ { "date": "2026-03-26T23:38:49.127865Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (1).| CWES updated (1)." }, { "date": "2026-03-26T23:38:53.089858Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-03-27T00:25:28.480175Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (1).| CWES updated (1)." }, { "date": "2026-03-27T00:25:32.552446Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-03-27T06:43:24.259016Z", "number": "5", "summary": "Source created.| CVE status created. (valid)| Description created for source." }, { "date": "2026-03-27T08:28:39.529238Z", "number": "6", "summary": "NCSC Score updated." }, { "date": "2026-03-27T19:41:45.542226Z", "number": "7", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (3).| CWES updated (1).| Vendor_assessment created." }, { "date": "2026-03-27T19:41:59.002463Z", "number": "8", "summary": "NCSC Score updated." }, { "date": "2026-03-27T19:47:34.966898Z", "number": "9", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (4).| CWES updated (1)." }, { "date": "2026-03-27T19:47:46.829885Z", "number": "10", "summary": "NCSC Score updated." }, { "date": "2026-03-27T20:56:12.116772Z", "number": "11", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-03-28T07:41:30.346861Z", "number": "12", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (5).| CWES updated (1)." }, { "date": "2026-03-30T12:41:42.908135Z", "number": "13", "summary": "Unknown change." }, { "date": "2026-04-01T18:27:48.337226Z", "number": "14", "summary": "Products connected (1).| Product Identifiers created (1)." }, { "date": "2026-04-01T18:27:50.653680Z", "number": "15", "summary": "NCSC Score updated." } ], "status": "interim", "version": "15" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<6.23.0", "product": { "name": "vers:unknown/<6.23.0", "product_id": "CSAFPID-5965579", "product_identification_helper": { "cpe": "cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*" } } } ], "category": "product_name", "name": "incus" } ], "category": "vendor", "name": "linuxcontainers" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<6.23.0", "product": { "name": "vers:unknown/<6.23.0", "product_id": "CSAFPID-5919453" } }, { "category": "product_version_range", "name": "vers:unknown/>=0|<6.23.0", "product": { "name": "vers:unknown/>=0|<6.23.0", "product_id": "CSAFPID-5944290" } } ], "category": "product_name", "name": "incus" } ], "category": "vendor", "name": "lxc" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-33898", "cwe": { "id": "CWE-303", "name": "Incorrect Implementation of Authentication Algorithm" }, "notes": [ { "category": "description", "text": "Incus is a system container and virtual machine manager. Prior to version 6.23.0, the web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted. `incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests. While the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL.\nThis allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`. This can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server. Version 6.23.0 patches the issue.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33898.json" }, { "category": "description", "text": "Incus is a system container and virtual machine manager. Prior to version 6.23.0, the web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted. `incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests. While the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL.\nThis allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`. This can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server. Version 6.23.0 patches the issue.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33898" }, { "category": "description", "text": "Incus is a system container and virtual machine manager. Prior to version 6.23.0, the web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted. `incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests. While the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL. This allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`. This can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server. Version 6.23.0 patches the issue.", "title": "debian - https://security-tracker.debian.org/tracker/CVE-2026-33898" }, { "category": "description", "text": "A flaw was found in Incus, a system container and virtual machine manager. The `incus webui` component incorrectly validates authentication tokens when they are passed in the URL. This vulnerability allows a local attacker, or a remote attacker who can trick a local user into interacting with the Incus UI web server, to gain unauthorized access. Successful exploitation could lead to privilege escalation or unauthorized access to Incus instances and potentially system resources.\nImportant: This flaw in the `incus webui` component allows for privilege escalation and unauthorized access. The vulnerability arises from improper authentication token validation when tokens are passed in the URL, enabling a local attacker or a remote attacker (via user interaction) to gain access to Incus instances and potentially system resources. Exploitation requires the `incus webui` server to be running and accessible.", "title": "redhat - https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33898.json" }, { "category": "description", "text": "### Summary\nThe web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted.\n\n### Details\n`incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests.\n\nWhile the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL.\nThis allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`.\n\nThis can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server.\n\n### Credit\nThis issue was discovered and reported by the team at [7asecurity](https://7asecurity.com/)", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGHSA-453r-g2pg-cxxq.json?alt=media" }, { "category": "description", "text": "### Summary\nThe web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted.\n\n### Details\n`incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests.\n\nWhile the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL.\nThis allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`.\n\nThis can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server.\n\n### Credit\nThis issue was discovered and reported by the team at [7asecurity](https://7asecurity.com/)", "title": "github - https://api.github.com/advisories/GHSA-453r-g2pg-cxxq" }, { "category": "other", "text": "0.00061", "title": "EPSS" }, { "category": "other", "text": "4.8", "title": "NCSC Score" }, { "category": "other", "text": "There is product data available from source Cveprojectv5", "title": "NCSC Score top increasing factors" }, { "category": "other", "text": "There is cwe data available from source Nvd", "title": "NCSC Score top decreasing factors" }, { "category": "details", "text": "Severity: 3\n", "title": "Vendor assessment" } ], "product_status": { "known_affected": [ "CSAFPID-5919453", "CSAFPID-5944290", "CSAFPID-5965579" ] }, "references": [ { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33898.json" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33898" }, { "category": "external", "summary": "Source - debian", "url": "https://security-tracker.debian.org/tracker/CVE-2026-33898" }, { "category": "external", "summary": "Source - redhat", "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33898.json" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Go%2FGHSA-453r-g2pg-cxxq.json?alt=media" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-453r-g2pg-cxxq" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd; osv; redhat", "url": "https://github.com/lxc/incus/security/advisories/GHSA-453r-g2pg-cxxq" }, { "category": "external", "summary": "Reference - redhat", "url": "https://www.cve.org/CVERecord?id=CVE-2026-33898" }, { "category": "external", "summary": "Reference - github; osv; redhat", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33898" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/lxc/incus/commit/d81d49e746e15dad35de39dc0ace0cedfba7d2f7" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/lxc/incus/releases/tag/v6.23.0" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-453r-g2pg-cxxq" } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "products": [ "CSAFPID-5919453", "CSAFPID-5944290", "CSAFPID-5965579" ] } ], "title": "CVE-2026-33898" } ] }