HIGH CVSS 7.7
Published: 2026-01-30

CVE-2026-25153

linuxfoundation backstage Security Advisory (CVE-2026-25153)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-25153 impacting linuxfoundation backstage. Evaluated with CVSS Base Score of 7.7 (HIGH).

Original NVD Description

Source: NIST NVD
Backstage is an open framework for building developer portals, and @backstage/plugin-techdocs-node provides common node.js functionalities for TechDocs. In versions of @backstage/plugin-techdocs-node prior to 1.13.11 and 1.14.1, 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. @backstage/plugin-techdocs-node versions 1.13.11 and 1.14.1 contain a fix. 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. Users of `@techdocs/cli` should also upgrade to the latest version, which includes the fixed `@backstage/plugin-techdocs-node` dependency. Some workarounds are available. Configure TechDocs with `runIn: docker` instead of `runIn: local` to provide container isolation, though it does not fully mitigate the risk. Limit who can modify `mkdocs.yml` files in repositories that TechDocs processes; only allow trusted contributors. Implement PR review requirements for changes to `mkdocs.yml` files to detect malicious `hooks` configurations before they are merged. Use MkDocs < 1.4.0 (e.g., 1.3.1) which does not support hooks. Note: This may limit access to newer MkDocs features. 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.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
High (AC:H)
Depends on race conditions or environment
Privileges Required
Low (PR:L)
Standard user access required
User Interaction
None (UI:N)
Zero human interaction required
Scope
Changed (S:C)
Impacts components beyond caller authority
Confidentiality
High (C:H)
Total information disclosure
Integrity
Low (I:L)
Partial data modification possible
Availability
Low (A:L)
Partial service performance degradation

🎯 Affected Versions Matrix

Affected Product linuxfoundation / backstage
Affected Versions *
Weakness Enumeration CWE-94

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2026-25153 impacting linuxfoundation backstage.

⚡ Nuclei Detection Template (YAML) cve-2026-25153.yaml
id: cve-2026-25153

info:
  name: linuxfoundation backstage - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-25153 affecting linuxfoundation backstage.
    Evaluation: Backstage is an open framework for building developer portals, and @backstage/plugin-techdocs-node provides common node.js functionalities for TechDoc...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-25153
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:L
    cvss-score: 7.7
    cve-id: CVE-2026-25153
    cwe-id: CWE-94
  tags: cve,cve-2026-25153,linuxfoundation,backstage,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "backstage"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-25153.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-25153
# Target: linuxfoundation backstage | CVSS: 7.7 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-25153 (linuxfoundation backstage)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against linuxfoundation backstage scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2026-25153.sh
# Recommended Remediation & Patching Commands for CVE-2026-25153
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install backstage 2>/dev/null || \
sudo dnf upgrade backstage 2>/dev/null || \
sudo yum update backstage

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i backstage 2>/dev/null || rpm -qa | grep -i backstage

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-25153 in linuxfoundation backstage?

Review vendor-specific security notices and update linuxfoundation backstage packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2026-25153?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2026-25153?

CVE-2026-25153 is classified with a CVSS 3.1 Base Score of 7.7 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.7
HIGH SEVERITY
CVE ID CVE-2026-25153
Weakness CWE-94
Vendor linuxfoundation
Product backstage
Published 2026-01-30
Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:L