CVE-2026-106556
CVE-2026-106556 is a high-severity vulnerability in Linuxfoundation Backstage with a CVSS 3.x base score of 7.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 7.7)
- EPSS exploit prediction: 0% (16th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Linuxfoundation Backstage
- Published:
- Last modified:
Description
Backstage is an open framework for building developer portals. Prior to 1.14.6, the @backstage/plugin-techdocs-node package is affected by configuration bypass in techdocs mkdocs.yml sanitization. Insufficient validation of MkDocs configuration during TechDocs generation could allow an authenticated user who can register or modify documentation sources to execute arbitrary commands in the build environment. Impact is limited to resources accessible to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
Frequently asked questions
- What is CVE-2026-106556?
- Backstage is an open framework for building developer portals. Prior to 1.14.6, the @backstage/plugin-techdocs-node package is affected by configuration bypass in techdocs mkdocs.yml sanitization. Insufficient validation of MkDocs configuration during TechDocs generation could allow an authenticated user who can register or modify documentation sources to execute arbitrary commands in the build environment. Impact is limited to resources accessible to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.
- How severe is CVE-2026-106556?
- CVE-2026-106556 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.
- Is CVE-2026-106556 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-106556?
- CVE-2026-106556 primarily affects Linuxfoundation Backstage. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-106556?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2026-106556 published?
- CVE-2026-106556 was published on 2026-10-07 and last updated on 2026-10-13.
References
- https://github.com/backstage/backstage/commit/25125ee727a3de3418a8fa6a9e458cd5b73ecf26
- https://github.com/backstage/backstage/commit/b6d1aea0bef99b8dfec3c8746032474867ba677a
- https://github.com/backstage/backstage/releases/tag/v1.50.5
- https://github.com/backstage/backstage/releases/tag/v1.54.6
- https://github.com/backstage/backstage/security/advisories/GHSA-g2hj-v2j6-vfvg
Affected products (7)
- cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage:1.51.0:-:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage:1.51.0:next0:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage:1.51.0:next1:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage:1.51.0:next2:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage:1.51.0:next3:*:*:*:*:*:*
- cpe:2.3:a:linuxfoundation:backstage_plugin-techdocs-node:*:*:*:*:*:*:*:*
More vulnerabilities in Linuxfoundation Backstage
- CVE-2026-106501 — Critical (CVSS 9.6): Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the…
- CVE-2026-106558 — High (CVSS 8.8): Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the…
- CVE-2026-88064 — High (CVSS 8.8): Backstage is an open framework for building developer portals. Prior to 1.14.6 and from 1.15.0 until 1.15.4, the…
- CVE-2026-106500 — High (CVSS 8.5): Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the…
- CVE-2026-106486 — High (CVSS 8.5): Backstage is an open framework for building developer portals. Prior to 0.3.10 in…
- CVE-2026-106459 — High (CVSS 8.5): Backstage is an open framework for building developer portals. From 0.3.0 until 0.3.8, the…
All CVEs affecting Linuxfoundation Backstage →
Other CWE-78 (OS Command Injection) vulnerabilities
- CVE-2026-100382 — Critical (CVSS 10.0): Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability in Wikimedia…
- CVE-2026-77521 — Critical (CVSS 10.0): MaxKB is an open-source AI assistant for enterprise. Prior to version 2.10.5-lts, assistants with a tool, MCP tool,…
- CVE-2026-82004 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Improper Neutralization of Special Elements used in an OS Command ('OS…
- CVE-2026-76197 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Improper Neutralization of Special Elements used in an OS Command ('OS…
- CVE-2026-76195 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Improper Neutralization of Special Elements used in an OS Command ('OS…
- CVE-2026-19188 — Critical (CVSS 10.0): A critical OS command injection vulnerability has been identified in the Haiwell IoT Cloud HMI Gateway product. The…