{"id":"CVE-2026-114622","state":"PUBLISHED","title":"baserCMS: Encoded path traversal bypass in the theme file API","description":"baserCMS is a website development framework. In versions 5.2.3 before 5.3.2 and 5.4.0 before 5.4.2, the optional BcThemeFile plugin's Admin API validates a raw path in ThemeFilesService::update() and getFullpath(), but ThemeFileForm::_execute() subsequently applies rawurldecode() to fullpath before writing. Because normalizePath() resolves only literal dot segments, percent-encoded traversal can pass the containment checks and become a path outside the theme directory at the write sink. An authenticated administrator can write PHP files into writable locations such as webroot and execute them, exceeding the intended theme-template editing boundary. The source also identifies the same check-before-decode ordering in ThemeFilesService::copy(), although that path was not dynamically verified. Exploitation requires the non-default plugin, an administrator session, and a same-origin Origin header; USE_CORE_ADMIN_API=false does not block session-authenticated requests. The Admin web form is not affected by this encoded-path tampering because FormProtection protects fullpath. This is a third bypass of the protections associated with CVE-2026-30940, using encoded traversal decoded after validation. This issue has been patched in versions 5.3.2 and 5.4.2.","publishedAt":"2026-10-23T13:41:33.272Z","updatedAt":"2026-10-30T20:04:28.351Z","severity":{"score":7.2,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["baserproject basercms"],"affected":[{"vendor":"baserproject","product":"basercms","versions":[{"version":">= 5.2.3, < 5.3.2","status":"affected"},{"version":">= 5.4.0, < 5.4.2","status":"affected"}]}],"references":["https://github.com/baserproject/basercms/security/advisories/GHSA-q7g3-qwrc-mp89","https://github.com/baserproject/basercms/commit/53ecf177dfb10eb1fb89c4b42d313983329aa162","https://github.com/baserproject/basercms/releases/tag/5.3.2","https://github.com/baserproject/basercms/releases/tag/5.4.2"],"weaknesses":["CWE-22","CWE-180"],"ingestedAt":"2026-10-30T20:14:06.645Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/114xxx/CVE-2026-114622.json","commit":"d7f5c3fe206091a44e450f13bfe51dc81b8a7843","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-114622","state":"PUBLISHED","datePublished":"2026-10-23T13:41:33.272Z","dateUpdated":"2026-10-30T20:04:28.351Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-21T20:34:25.600Z"},"containers":{"cna":{"title":"baserCMS: Encoded path traversal bypass in the theme file API","descriptions":[{"lang":"en","value":"baserCMS is a website development framework. In versions 5.2.3 before 5.3.2 and 5.4.0 before 5.4.2, the optional BcThemeFile plugin's Admin API validates a raw path in ThemeFilesService::update() and getFullpath(), but ThemeFileForm::_execute() subsequently applies rawurldecode() to fullpath before writing. Because normalizePath() resolves only literal dot segments, percent-encoded traversal can pass the containment checks and become a path outside the theme directory at the write sink. An authenticated administrator can write PHP files into writable locations such as webroot and execute them, exceeding the intended theme-template editing boundary. The source also identifies the same check-before-decode ordering in ThemeFilesService::copy(), although that path was not dynamically verified. Exploitation requires the non-default plugin, an administrator session, and a same-origin Origin header; USE_CORE_ADMIN_API=false does not block session-authenticated requests. The Admin web form is not affected by this encoded-path tampering because FormProtection protects fullpath. This is a third bypass of the protections associated with CVE-2026-30940, using encoded traversal decoded after validation. This issue has been patched in versions 5.3.2 and 5.4.2."}],"affected":[{"vendor":"baserproject","product":"basercms","versions":[{"version":">= 5.2.3, < 5.3.2","status":"affected"},{"version":">= 5.4.0, < 5.4.2","status":"affected"}]}],"references":[{"url":"https://github.com/baserproject/basercms/security/advisories/GHSA-q7g3-qwrc-mp89","name":"https://github.com/baserproject/basercms/security/advisories/GHSA-q7g3-qwrc-mp89","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/baserproject/basercms/commit/53ecf177dfb10eb1fb89c4b42d313983329aa162","name":"https://github.com/baserproject/basercms/commit/53ecf177dfb10eb1fb89c4b42d313983329aa162","tags":["x_refsource_MISC"]},{"url":"https://github.com/baserproject/basercms/releases/tag/5.3.2","name":"https://github.com/baserproject/basercms/releases/tag/5.3.2","tags":["x_refsource_MISC"]},{"url":"https://github.com/baserproject/basercms/releases/tag/5.4.2","name":"https://github.com/baserproject/basercms/releases/tag/5.4.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.2,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","lang":"en","description":"CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-180","lang":"en","description":"CWE-180: Incorrect Behavior Order: Validate Before Canonicalize","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-23T13:41:33.272Z"},"source":{"advisory":"GHSA-q7g3-qwrc-mp89","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/baserproject/basercms/security/advisories/GHSA-q7g3-qwrc-mp89","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-30T20:04:21.764955Z","id":"CVE-2026-114622","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-30T20:04:28.351Z"}}]}}}