Summary
Workarounds
- Run Backstage in a containerised environment with limited filesystem access
- Restrict template creation to trusted users
Impact
The resolveSafeChildPath utility function in @backstage/backend-plugin-api, which is used to prevent path traversal attacks, failed to properly validate symlink chains and dangling symlinks. An attacker could bypass the path validation by:
- Symlink chains: Creating
link1 → link2 → /outsidewhere intermediate symlinks eventually resolve outside the allowed directory - Dangling symlinks: Creating symlinks pointing to non-existent paths outside the base directory, which would later be created during file operations
This function is used by Scaffolder actions and other backend components to ensure file operations stay within designated directories.
CVE-2026-24047 has a CVSS score of 6.3 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.1.17); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
This vulnerability is fixed in @backstage/backend-plugin-api version 0.1.17. Users should upgrade to this version or later.
Frequently Asked Questions
- What is CVE-2026-24047? CVE-2026-24047 is a medium-severity security vulnerability in @backstage/cli-common (npm), affecting versions <= 0.1.16. It is fixed in 0.1.17.
- How severe is CVE-2026-24047? CVE-2026-24047 has a CVSS score of 6.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of @backstage/cli-common are affected by CVE-2026-24047? @backstage/cli-common (npm) versions <= 0.1.16 is affected.
- Is there a fix for CVE-2026-24047? Yes. CVE-2026-24047 is fixed in 0.1.17. Upgrade to this version or later.
- Is CVE-2026-24047 exploitable, and should I be worried? Whether CVE-2026-24047 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-24047 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-24047? Upgrade
@backstage/cli-commonto 0.1.17 or later.