CVE-2026-75593: BuildKit: Malicious client can bypass destination directory validation on local sources upload
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to 0.31.2, a custom client can produce such an upload request to the BuildKit daemon that files can escape from the BuildKit-controlled state directory. The client needs to have valid permissions to access BuildKit control API to issue builds, eg., bypass authentication, etc. This issue is fixed in version 0.31.2.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
BuildKitto a version that resolves this vulnerability.Fixed in 0.31.2
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker needs valid permission to access the BuildKit control API and issue builds. This includes a client that can bypass authentication or otherwise obtain authorized BuildKit API access.
What is the impact of a successful exploit?
A malicious custom client can craft a local-source upload request that bypasses destination-directory validation, allowing files to escape the BuildKit-controlled state directory.
Which versions should be remediated?
BuildKit versions prior to 0.31.2 are affected. Upgrade to version 0.31.2 to obtain the fix.