Quick answers
- Is CVE-2026-13723 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-13723 being exploited in the wild.
- How severe is CVE-2026-13723?
- Informational severity, with a CVSS score of 0, published 29 July 2026.
- Which products and versions are affected?
- Develar app-builder <= 4.2.0.
- Is there a fix for CVE-2026-13723?
- A patch was published on 2026-07-08: Community pull request with fix submitted to GitHub repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-13723 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2026-13723?
- Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A vulnerability exists in the `zipx.Unzip` extraction routine of Develar's app-builder (up to version 4.2.0) due to improper path validation on macOS APFS volumes. The issue stems from a combination of CWE-22 (Path Traversal) and CWE-59 (Link Following) where the application fails to perform canonical Unicode normalization before validating paths. Because APFS treats certain Unicode-equivalent characters as identical (e.g., 'ß' and 'ss'), an attacker can craft a ZIP archive containing a symlink (e.g., named 'ss') pointing to a sensitive system file, followed by a regular file using a colliding Unicode name (e.g., 'ß'). During extraction, the second file write follows the previously created symlink, overwriting the target file. A community-provided fix involves enforcing directory containment for symlinks and using the O_NOFOLLOW flag during file writes.
Affected products
- Develar app-builder <= 4.2.0
Timeline
- 2026-05-27: other: Vendor notified by CERT/CC
- 2026-07-08: patched: Community pull request with fix submitted to GitHub repository
- 2026-07-29: disclosed: Vulnerability publicly disclosed by CERT/CC and NVD