CVE-2026-25153 — @backstage/plugin-techdoc…
HIGHCVE-2026-25153 is a high-severity (CVSS 7.7) Code Injection vulnerability in @backstage/plugin-techdocs-node. A fix is available for @backstage/plugin-techdocs-node — see the affected versions and patch details below.
@backstage/plugin-techdocs-node vulnerable to arbitrary code execution via MkDocs hooks
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-25153.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-25153 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@backstage/plugin-techdocs-nodenpmDescription
Impact
When TechDocs is configured with runIn: local, a malicious actor who can submit or modify a repository's mkdocs.yml file can execute arbitrary Python code on the TechDocs build server via MkDocs hooks configuration.
Patches
Upgrade to @backstage/plugin-techdocs-node version 1.13.11, 1.14.1 or later.
The fix introduces an allowlist of supported MkDocs configuration keys. Unsupported configuration keys (including hooks) are now removed from mkdocs.yml before running the generator, with a warning logged to indicate which keys were removed.
Note: Users of @techdocs/cli should also upgrade to the latest version, which includes the fixed @backstage/plugin-techdocs-node dependency.
Workarounds
If you cannot upgrade immediately:
- Use Docker mode with restricted access: Configure TechDocs with
runIn: dockerinstead ofrunIn: local. This provides container isolation, though it does not fully mitigate the risk. - Restrict repository access: Limit who can modify
mkdocs.ymlfiles in repositories that TechDocs processes. Only allow trusted contributors. - Manual review: Implement PR review requirements for changes to
mkdocs.ymlfiles to detect malicioushooksconfigurations before they are merged. - Downgrade MkDocs: Use MkDocs < 1.4.0 (e.g., 1.3.1) which does not support hooks. Note: This may limit access to newer MkDocs features.
Note: Building documentation in CI/CD pipelines using @techdocs/cli does not mitigate this vulnerability, as the CLI uses the same vulnerable @backstage/plugin-techdocs-node package.
References
MkDocs Hooks Documentation MkDocs 1.4 Release Notes TechDocs Architecture
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @backstage/plugin-techdocs-node | ≥ 1.14.0&&< 1.14.1 | 1.14.1npm install @backstage/plugin-techdocs-node@1.14.1 |
| 📦npm | @backstage/plugin-techdocs-node | all versions | 1.13.11npm install @backstage/plugin-techdocs-node@1.13.11 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @backstage/plugin-techdocs-node, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @backstage/plugin-techdocs-node to 1.14.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-25153 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-25153 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-25153. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Developer Hub 1.8 | rhdh/rhdh-hub-rhel9:1774545605 | RHSA-2026:6174 |
| Red Hat Developer Hub 1.9 | rhdh/rhdh-hub-rhel9:1775140647 | RHSA-2026:6802 |
Frequently Asked Questions
Is CVE-2026-25153 in your dependencies?
O3 Security finds CVE-2026-25153 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.