Sharp is Vulnerable to Path Traversal via Unsanitized Extension in FileUtil

Exploitation

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

CVSS

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

EPSS

• CVE-2026-33686: 0.56% estimated exploitation activity in the next 30 days; percentile 46.49 (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 A path traversal vulnerability exists in the FileUtil class of the code16/sharp package. The application fails to sanitize file extensions properly, allowing path separators to be passed into the storage layer. Detail In src/Utils/FileUtil.php, the FileUtil::explodeExtension() function extracts a file's extension by splitting the filename at the last dot. However, the extracted extension is never sanitized. While the application uses a normalizeName() function, this function only cleans the base filename, meaning any path separators (such as /) injected into the extension will survive and be passed into the storeAs() function. Impact Exploiting this flaw allows an authenticated attacker to manipulate file paths: - Files can be written outside of the intended tmp directory via path traversal. For more details on the package, visit: https://github.com/code16/sharp - Existing critical files (such as .env or configuration files) could potentially be overwritten. Review the CWE…

Published by the source

25 Mar 2026, 20:01 UTC

Last modified by the source

27 Mar 2026, 21:36 UTC

Source last checked

26 Oct 2026, 14:39 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9ffq-6457-8958

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-33686

Advisory: Sharp is Vulnerable to Path Traversal via Unsanitized Extension in FileUtil
IDs: CVE-2026-33686, GHSA-9ffq-6457-8958
Record: https://patchnext.com/advisories/cve-2026-33686 (revision 1, source checked 26 Oct 2026, 14:39 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code16/sharp 9.20.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist code16/sharp: affected < 9.20.0; fixed in 9.20.0

## Suggested inspection (read-only)
- Packagist code16/sharp: 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 code16/sharp.
- 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-9ffq-6457-8958 (GitHub-reviewed advisory GHSA-9ffq-6457-8958 lists affected ranges: Packagist code16/sharp >=0 <9.20.0)

Commands are suggestions: review each one before running it.