BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to 0.31.1, a custom frontend could place an invalid SecurityMode value in a crafted build request, and executor/oci/spec_linux.go treated the unsupported value as a non-sandbox mode without requiring the security.insecure entitlement. This disabled Seccomp and AppArmor protections for the build container even though Linux capabilities remained restricted. This issue is fixed in version 0.31.1.
https://github.com/moby/buildkit/security/advisories/GHSA-7236-3392-c5c6
https://github.com/moby/buildkit/releases/tag/v0.31.1
https://github.com/moby/buildkit/commit/64bbec89ca43dd95b2853edeca240c33c6729910
https://github.com/moby/buildkit/commit/3ea6dd0ce7d269cdb8aa23348718e2c1bf64f109
Published: 2026-08-19
Updated: 2026-08-19
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity: Critical
Base Score: 5.3
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Severity: Medium