CVE-2026-106558
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.
Does this matter?
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.
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.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.47% probability · 40th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- linuxfoundation/backstage plugin-techdocs-node · linuxfoundation/backstage
- Source
- security-advisories@github.com
EPSS moved from 0.5% on 8 October 2026 to 0.5% on 26 October 2026.
References
- https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91bPatch
- https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709Patch
- https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310cPatch
- https://github.com/backstage/backstage/releases/tag/v1.50.7Patch, Release Notes
- https://github.com/backstage/backstage/releases/tag/v1.54.9Patch, Release Notes
- https://github.com/backstage/backstage/releases/tag/v1.55.2Patch, Release Notes
- https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99gMitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.