{"id":"CVE-2026-106558","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-106558","generatedAt":"2026-10-28T03:38:43.114Z","title":"Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration.","description":"Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1.","published":"2026-10-07T15:17:16.000Z","lastModified":"2026-10-13T14:25:12.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-502"],"affected":["linuxfoundation/backstage plugin-techdocs-node","linuxfoundation/backstage"],"epss":{"score":0.00469,"percentile":0.40428,"date":"2026-10-27","history":[{"date":"2026-10-08","score":0.00471,"percentile":0.3879}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-07T15:17:16.000Z","detail":{"score":"8.8","severity":"HIGH","publishedAt":"2026-10-07T15:17:15.713Z"},"summary":"New CVE, high severity (CVSS 8.8)."}],"references":[{"url":"https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/releases/tag/v1.50.7","tags":["Patch","Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/releases/tag/v1.54.9","tags":["Patch","Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/releases/tag/v1.55.2","tags":["Patch","Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g","tags":["Mitigation","Vendor Advisory"],"source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-106558","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}