decompress: Arbitrary File Write via Archive Extraction (Zip Slip)

Exploitation

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

CVSS 4.0

5.6 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:P · score source

EPSS

• CVE-2026-10732: 0.52% estimated exploitation activity in the next 30 days; percentile 44.28 (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.

All versions of the package decompress are vulnerable to Arbitrary File Write via Archive Extraction (Zip Slip) when extracting a ZIP archive containing two entries with the same path - the first being a symlink to an arbitrary target and the second being a regular file - the file content is written through the symlink to the target location outside the output directory. This is due to the microtask processing order that checks readlink for the second file before resolving symlink for the first file. An attacker can write arbitrary files on the host filesystem potentially leading to remote code execution by providing a specially crafted ZIP archive. Note: This bypasses all existing path traversal protections including preventWritingThroughSymlink, added as a part of the fix for CVE-2020-12265.

Published by the source

5 Jun 2026, 09:33 UTC

Last modified by the source

13 Aug 2026, 05:15 UTC

Source last checked

26 Oct 2026, 13:00 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-h39j-r5qq-r9mm

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-h39j-r5qq-r9mm

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# Patch Next advisory brief: CVE-2026-10732

Advisory: decompress: Arbitrary File Write via Archive Extraction (Zip Slip)
IDs: CVE-2026-10732, GHSA-h39j-r5qq-r9mm
Record: https://patchnext.com/advisories/cve-2026-10732 (revision 3, source checked 26 Oct 2026, 13:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm decompress: affected <= 4.2.1

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

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on decompress.
- 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-h39j-r5qq-r9mm (OSV record GHSA-h39j-r5qq-r9mm lists affected ranges: npm decompress >=0 <=4.2.1)
- Verified: https://github.com/advisories/GHSA-h39j-r5qq-r9mm (GitHub-reviewed advisory GHSA-h39j-r5qq-r9mm lists affected ranges: npm decompress >=0 <=4.2.1)

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