Code Extension Marketplace: Zip Slip Path Traversal

Exploitation

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

CVSS 4.0

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

EPSS

• CVE-2026-35454: 0.35% estimated exploitation activity in the next 30 days; percentile 28.63 (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.

Zip Slip Path Traversal in coder/code-marketplace Summary A Zip Slip (CWE-22) vulnerability in coder/code-marketplace ≤ v2.4.1 allowed a malicious VSIX file to write arbitrary files outside the extension directory. ExtractZip passed raw zip entry names to a callback that wrote files via filepath.Join with no boundary check; filepath.Join resolved .. components but did not prevent the result from escaping the base path. Root Cause ExtractZip passed the raw, attacker-controlled zf.Name to a caller-supplied callback: AddExtension constructed the output path with filepath.Join and no boundary check: filepath.Clean resolved .. lexically but did not confine the result to dir: Attack Scenario An authenticated user (any upload-capable role) would submit a VSIX containing path-traversal entries. On extraction, files would land at attacker-chosen paths writable by the marketplace process, enabling persistence (cron/init injection), SSH key injection, ld.so.preload hijacking, or binary…

Published by the source

4 Apr 2026, 06:26 UTC

Last modified by the source

7 Apr 2026, 14:21 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8x9r-hvwg-c55h

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# Patch Next advisory brief: CVE-2026-35454

Advisory: Code Extension Marketplace: Zip Slip Path Traversal
IDs: CVE-2026-35454, GHSA-8x9r-hvwg-c55h
Record: https://patchnext.com/advisories/cve-2026-35454 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/coder/code-marketplace 1.2.3-0.20260402184705-988440dee05f. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/coder/code-marketplace: affected < 1.2.3-0.20260402184705-988440dee05f; fixed in 1.2.3-0.20260402184705-988440dee05f

## Suggested inspection (read-only)
- Go github.com/coder/code-marketplace: check the installed version with your package manager.

## 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 github.com/coder/code-marketplace.
- 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://github.com/advisories/GHSA-8x9r-hvwg-c55h (GitHub-reviewed advisory GHSA-8x9r-hvwg-c55h lists affected ranges: Go github.com/coder/code-marketplace >=0 <1.2.3-0.20260402184705-988440dee05f)

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