node-tar: Uncaught Exception DoS via NUL byte in PAX path/linkpath records

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS

• CVE-2026-59875: 0.35% estimated exploitation activity in the next 30 days; percentile 29.20 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary node-tar strips trailing NUL bytes from long-name (L) and long-linkpath (K) GNU extended headers but does not apply the same sanitization to equivalent fields delivered via PAX (x typeflag) extended headers. A PAX record of the form path=visible.txt\x00hidden.txt is parsed verbatim into entry.path and flows into fs.lstat() / fs.open(), which Node.js core rejects with ERRINVALIDARGVALUE. The throw originates inside an FSReqCallback async chain that is not wrapped by the consumer's await/try-catch around tar.x() — it surfaces as uncaughtException and terminates the process. This is a remote denial-of-service primitive against any process that extracts attacker-supplied tarballs through tar.x / tar.extract / tar.t / tar.Parser, even when the consumer follows the documented try/catch error-handling pattern. A secondary parser-differential (CWE-436) exists because tar(1), bsdtar, and Python tarfile truncate the path at the first NUL (yielding visible.txt) while node-tar retains…

Published by the source

20 Jul 2026, 21:51 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:57 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-gvwx-54wh-qm9j

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-gvwx-54wh-qm9j

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# Patch Next advisory brief: CVE-2026-59875

Advisory: node-tar: Uncaught Exception DoS via NUL byte in PAX path/linkpath records
IDs: CVE-2026-59875, GHSA-gvwx-54wh-qm9j
Record: https://patchnext.com/advisories/cve-2026-59875 (revision 2, source checked 26 Oct 2026, 12:57 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: tar 7.5.17. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm tar: affected <= 7.5.16; fixed in 7.5.17

## Suggested inspection (read-only)
- `npm ls tar --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on tar.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-gvwx-54wh-qm9j (OSV record GHSA-gvwx-54wh-qm9j lists affected ranges: npm tar >=0 <7.5.17 (fixed))
- Verified: https://github.com/advisories/GHSA-gvwx-54wh-qm9j (GitHub-reviewed advisory GHSA-gvwx-54wh-qm9j lists affected ranges: npm tar >=0 <=7.5.16)

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