CVE-2026-50015

pnpm Vulnerable to Arbitrary File Write/Delete via Malicious Patch File (Path Traversal)

case 'file creation': {
  const eff = effect
  fs.ensureDirSync(dirname(eff.path))
  fs.writeFileSync(eff.path, fileContents, { mode: eff.mode })
  break
}

case 'file deletion': {
  const eff = effect
  // TODO: integrity checks
  if (!opts.dryRun) {
    fs.unlinkSync(eff.path)
  }
  break
}

# Write variant:
bash autofyn_audit/exploits/vuln6_patch_traversal_write/exploit.sh
# Result: PASS -- /tmp/vuln6_pwned created with attacker-controlled content

# Delete variant:
bash autofyn_audit/exploits/vuln7_patch_traversal_delete/exploit.sh
# Result: PASS -- /tmp/vuln7_target deleted by malicious patch

# Combined chain (delete + replace SSH authorized_keys):
bash autofyn_audit/exploits/chain2_patch_ssh_backdoor/exploit.sh
# Result: PASS -- authorized_keys replaced with attacker's public key

Arbitrary file write and delete as the user running pnpm install, limited to paths writable by that user. An attacker who submits a PR adding a .patch file and patchedDependencies config can target SSH authorized_keys, shell configuration, CI/CD files, or other writable files. Patch files may receive less review scrutiny than package.json changes because the ../ traversal sequences are in diff --git headers that look like patch metadata.

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-50015 has a CVSS score of 7.3 (High). The vector is network-reachable, low privileges required, and user interaction required. 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 (10.34.0, 11.4.0); upgrading removes the vulnerable code path.

Kodem intelligence

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1. What is CVE-2026-50015? CVE-2026-50015 is a high-severity path traversal vulnerability in pnpm (npm), affecting versions < 10.34.0. It is fixed in 10.34.0, 11.4.0. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-50015? CVE-2026-50015 has a CVSS score of 7.3 (High). 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.
3. Which versions of pnpm are affected by CVE-2026-50015? pnpm (npm) versions < 10.34.0 is affected.
4. Is there a fix for CVE-2026-50015? Yes. CVE-2026-50015 is fixed in 10.34.0, 11.4.0. Upgrade to this version or later.
5. Is CVE-2026-50015 exploitable, and should I be worried? Whether CVE-2026-50015 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
6. What actually determines whether CVE-2026-50015 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.
7. How do I fix CVE-2026-50015?
   • Upgrade pnpm to 10.34.0 or later
   • Upgrade pnpm to 11.4.0 or later

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