BuildKit's cache mount source= selector on Windows Container on Windows (WCOW) workers does not detect NTFS directory junctions placed inside the cache root. A build authored by an untrusted user on a WCOW-configured BuildKit daemon can read arbitrary host files reachable to the BuildKit daemon process.
https://github.com/moby/buildkit/security/advisories/GHSA-388v-wmr2-g2v2
Published: 2026-07-20
Updated: 2026-08-05
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Severity: High
Base Score: 5.6
Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00145