{
  "affected": [
    {
      "affectedData": [
        {
          "product": "pnpm",
          "vendor": "pnpm",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 10.34.0"
            },
            {
              "status": "affected",
              "version": "\u003e= 11.0.0, \u003c 11.4.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "pnpm is a package manager. Prior to 10.34.0 and 11.4.0, pnpm\u0027s tarball extraction worker skips integrity verification when the integrity field is absent from the lockfile resolution. If an attacker can both modify pnpm-lock.yaml to remove the integrity: field and cause the referenced registry URL to serve altered package content, pnpm install --frozen-lockfile can install the altered package without an integrity error. npm\u0027s npm ci enforces integrity by default; pnpm\u0027s behavior of silently skipping verification is a pnpm-specific fail-open gap. This vulnerability is fixed in 10.34.0 and 11.4.0."
    }
  ],
  "id": "CVE-2026-50021",
  "lastModified": "2026-06-26T05:16:29.323",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-50021",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-25T00:00:00+00:00",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-25T18:16:39.557",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/pnpm/pnpm/security/advisories/GHSA-q6j5-fjx5-2mc3"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/pnpm/pnpm/security/advisories/GHSA-q6j5-fjx5-2mc3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Undergoing Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-354"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "pnpm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "11.0.0"
            },
            {
              "fixed": "11.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "pnpm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.34.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-50021"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-354"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-26T22:53:01Z",
    "nvd_published_at": "2026-06-25T18:16:39Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\npnpm\u0027s tarball extraction worker skips integrity verification when the `integrity` field is absent from the lockfile resolution. If an attacker can both modify `pnpm-lock.yaml` to remove the `integrity:` field and cause the referenced registry URL to serve altered package content, `pnpm install --frozen-lockfile` can install the altered package without an integrity error. npm\u0027s `npm ci` enforces integrity by default; pnpm\u0027s behavior of silently skipping verification is a pnpm-specific fail-open gap.\n\n## Vulnerability Details\n\nThe `addTarballToStore` function in `worker/src/start.ts` (lines 189-204) checks `if (integrity)` before verifying the tarball hash. The `TarballResolution` type declares `integrity` as optional (`integrity?: string`). When the lockfile omits the `integrity` field, the guard evaluates to `false`, skipping hash verification entirely. The worker then computes a new hash from the unverified content and stores it as legitimate.\n\n```typescript\n// worker/src/start.ts:189-204\nfunction addTarballToStore ({ buffer, storeDir, integrity, ... }: TarballExtractMessage) {\n  if (integrity) {           // false when integrity is undefined\n    const { algorithm, hexDigest } = parseIntegrity(integrity)\n    const calculatedHash = crypto.hash(algorithm, buffer, \u0027hex\u0027)\n    if (calculatedHash !== hexDigest) {\n      return { status: \u0027error\u0027, error: { type: \u0027integrity_validation_failed\u0027, ... } }\n    }\n  }\n  return {\n    status: \u0027success\u0027,\n    value: { integrity: integrity ?? calcIntegrity(buffer) },\n  }\n}\n```\n\n## Proof of Concept\n\n```bash\nbash autofyn_audit/exploits/vuln1_integrity_bypass/exploit.sh\n# Publishes a package, generates lockfile, republishes tampered version,\n# strips integrity field, re-runs install --frozen-lockfile.\n# Result: PASS -- tampered package installed without integrity error.\n```\n\n## Impact\n\nSupply chain compromise in environments where an attacker can both alter the lockfile and cause the referenced registry URL to serve altered package content. The `--frozen-lockfile` flag does not fail closed when the integrity field is missing.\n\n## Suggested Remediation\n\nRequire an `integrity` field for remote tarball resolutions. Change the `if (integrity)` guard to fail when integrity is absent for non-local packages. When `--frozen-lockfile` is active, reject lockfile entries that lack integrity for remote packages.\n\n---\n\n\u003e Discovered by [AutoFyn](https://github.com/SignalPilot-Labs/AutoFyn)\n\u003e Full audit report: [audit_report.md](https://github.com/tempcollab/pnpm/blob/main/autofyn_audit/audit_report.md)\n\u003e Exploit script: [exploit.sh](https://github.com/tempcollab/pnpm/blob/main/autofyn_audit/exploits/vuln1_integrity_bypass/exploit.sh)",
  "id": "GHSA-q6j5-fjx5-2mc3",
  "modified": "2026-06-26T22:53:01Z",
  "published": "2026-06-26T22:53:01Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pnpm/pnpm/security/advisories/GHSA-q6j5-fjx5-2mc3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50021"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pnpm/pnpm"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "pnpm Has an Integrity Check Bypass via Missing Lockfile Integrity Field"
}