Quick answers
- Is CVE-2026-15789 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-15789 being exploited in the wild.
- How severe is CVE-2026-15789?
- Informational severity, with a CVSS score of 6.9, published 21 July 2026.
- Which products and versions are affected?
- Moby Project BuildKit < 0.31.2.
- Is there a fix for CVE-2026-15789?
- A patch was published on 2026-07-21: Fix released in version 0.31.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-15789 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2026-15789?
- Check whether you run Moby Project BuildKit at an affected version. 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 path traversal vulnerability (CWE-22) exists in the BuildKit daemon's handling of local source upload requests. By crafting a malicious upload request using a custom client, an attacker can bypass destination directory validation to write files outside of the BuildKit-controlled state directory. Exploitation requires the attacker to have valid permissions to access the BuildKit control API. The vulnerability is addressed in BuildKit version 0.31.2. Users are advised to upgrade or restrict API access to trusted clients like Docker Buildx or buildctl.
Affected products
- Moby BuildKit < 0.31.2
Timeline
- 2026-07-16: advisory: GitHub Security Advisory published by Moby project
- 2026-07-21: disclosed: CVE-2026-15789 published to NVD
- 2026-07-21: patched: Fix released in version 0.31.2