CVE-2026-50014: pnpm Git Fetch Argument Injection Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-p4xf-rf54-rj3x",
  "modified" : "2026-06-26T22:53:21Z",
  "published" : "2026-06-26T22:53:21Z",
  "aliases" : [ "CVE-2026-50014" ],
  "summary" : "pnpm: Git Fetch Argument Injection via Lockfile resolution.commit",
  "details" : "## Summary\n\npnpm passes the lockfile-controlled git `resolution.commit` value to `git fetch` without a `--` separator or commit-format validation. For git dependencies fetched through the shallow-fetch path, a malicious lockfile can replace the expected 40-character commit hash with a Git option such as `--upload-pack=<command>`. For SSH and local transports, `--upload-pack` can execute the supplied command. HTTPS transports ignore `--upload-pack`, so the practical attack surface is primarily SSH or local git dependencies.\n\n## Vulnerability Details\n\nThe vulnerable path is in `fetching/git-fetcher/src/index.ts`. When a git dependency host is configured for shallow fetching, pnpm calls:\n\n```typescript\nawait execGit(['fetch', '--depth', '1', 'origin', resolution.commit], { cwd: tempLocation })\n```\n\nBecause `resolution.commit` is appended before a `--` separator, Git can parse a commit value beginning with `-` as an option. The same file later passes the value to `git checkout` without a separator:\n\n```typescript\nawait execGit(['checkout', resolution.commit], { cwd: tempLocation })\n```\n\n`resolution.commit` comes from the lockfile and is typed as a plain `string`; pnpm does not validate it as a 40-character hexadecimal commit before passing it to Git.\n\n## Proof of Concept\n\n```bash\nbash autofyn_audit/exploits/vuln11_git_upload_pack_rce/exploit.sh\n# Creates a local bare git repo and triggers the shallow-fetch path.\n# Replaces the lockfile commit hash with '--upload-pack=touch /tmp/vuln11_pwned'.\n# Result: PASS -- /tmp/vuln11_pwned created by injected touch command.\n```\n\nThe PoC uses a local `file://githost/...` repository because the injection requires a local or SSH transport. HTTPS transport ignores `--upload-pack`.\n\n## Impact\n\nCode execution as the user running `pnpm install`, under specific transport conditions. The attacker must modify `pnpm-lock.yaml`, and the affected dependency must use SSH or local git transport. HTTPS transport (the common case) is immune.\n\n## Suggested Remediation\n\nAdd a `--` separator before lockfile-controlled git revision values. Validate `resolution.commit` matches `/^[0-9a-f]{40}$/i` before passing to Git.\n\n---\n\n> Discovered by [AutoFyn](https://github.com/SignalPilot-Labs/AutoFyn)\n> Full audit report: [audit_report.md](https://github.com/tempcollab/pnpm/blob/main/autofyn_audit/audit_report.md)\n> Exploit script: [exploit.sh](https://github.com/tempcollab/pnpm/blob/main/autofyn_audit/exploits/vuln11_git_upload_pack_rce/exploit.sh)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "pnpm"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "10.34.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "pnpm"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0"
      }, {
        "fixed" : "11.4.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/pnpm/pnpm/security/advisories/GHSA-p4xf-rf54-rj3x"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-50014"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pnpm/pnpm"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-88" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-26T22:53:21Z",
    "nvd_published_at" : "2026-06-25T18:16:39Z"
  }
}