CVE-2026-15788

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/moby/buildkit/security/advisories/GHSA-388v-wmr2-g2v2	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mobyproject:buildkit:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-20 20:16

Updated : 2026-08-05 19:45

NVD link : CVE-2026-15788

Mitre link : CVE-2026-15788

CVE.ORG link : CVE-2026-15788

JSON object : View

Products Affected

mobyproject

buildkit

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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