A malicious image can advertise DiffIDs from another image while containing different layer contents. In affected versions, BuildKit could use the advertised DiffIDs to derive cache and snapshot identity without validating that they matched the actual layer contents.
If a BuildKit daemon with shared or persistent cache first processes such a malicious image, a later build using the victim image may mount the attacker-controlled layer contents as the base image. This can allow code from the malicious image to run in the victim build, for example by replacing a commonly executed path such as /bin/sh. The attacker-controlled code may read build secrets mounted into the build, access other build resources, alter output artifacts, or hang the build.
The issue affects both regular snapshotters and lazy-pulling snapshotters such as stargz.
Metrics
Affected Vendors & Products
References
History
Mon, 05 Oct 2026 21:15:00 +0000
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Moby
Moby buildkit |
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| Vendors & Products |
Moby
Moby buildkit |
Mon, 05 Oct 2026 20:30:00 +0000
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| Metrics |
ssvc
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Mon, 05 Oct 2026 18:00:00 +0000
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| Description | A malicious image can advertise DiffIDs from another image while containing different layer contents. In affected versions, BuildKit could use the advertised DiffIDs to derive cache and snapshot identity without validating that they matched the actual layer contents. If a BuildKit daemon with shared or persistent cache first processes such a malicious image, a later build using the victim image may mount the attacker-controlled layer contents as the base image. This can allow code from the malicious image to run in the victim build, for example by replacing a commonly executed path such as /bin/sh. The attacker-controlled code may read build secrets mounted into the build, access other build resources, alter output artifacts, or hang the build. The issue affects both regular snapshotters and lazy-pulling snapshotters such as stargz. | |
| Title | Cache poisoning via unvalidated image layer DiffIDs | |
| Weaknesses | CWE-354 | |
| References |
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| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: Docker
Published: 2026-10-05T17:45:39.491Z
Updated: 2026-10-05T19:06:41.297Z
Reserved: 2026-09-17T17:17:49.216Z
Link: CVE-2026-93318
Updated: 2026-10-05T19:06:37.814Z
Status : Awaiting Analysis
Published: 2026-10-05T18:17:38.080
Modified: 2026-10-06T15:08:38.397
Link: CVE-2026-93318
No data.