CVE-2026-24843: chainguard-dev melange Path Traversal

Vulnerability summary

CVE-2026-24843 is a high (CVSS 8.4) Path Traversal vulnerability in chainguard-dev melange. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 8% of scored vulnerabilities.

Timeline

1. 04-02-2026
   PublishedVulnerability first disclosed.
2. 05-02-2026
   Last modifiedVulnerability information updated.

Description

melange allows users to build apk packages using declarative pipelines. In version 0.11.3 to before 0.40.3, an attacker who can influence the tar stream from a QEMU guest VM could write files outside the intended workspace directory on the host. The retrieveWorkspace function extracts tar entries without validating that paths stay within the workspace, allowing path traversal via ../ sequences. This issue has been patched in version 0.40.3.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.