Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-93318— Cache poisoning via unvalidated image layer DiffIDs

Quick assessment

Affected
moby BuildKit
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

恶意镜像可以声明来自另一张镜像的 DiffID（差异层标识），但其实际层内容却不同。在受影响的版本中，BuildKit 可能会使用这些声明的 DiffID 来推导缓存和快照标识，而未验证它们是否与实际的层内容相匹配。 如果拥有共享或持久缓存的 BuildKit 守护进程首先处理了此类恶意镜像，后续使用受害镜像的构建过程可能会将攻击者控制的层内容挂载为基础镜像。这使得恶意镜像中的代码能够在受害者的构建过程中运行，例如通过替换频繁执行的路径（如 /bin/sh）。攻击者控制的代码可能读取挂载到构建过程中的构建密钥、访问

CVSS 7.5 · High

Affected Version Matrix 1

VendorProduct Version RangeStatus
moby BuildKit < 0.33.1 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-93318

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Cache poisoning via unvalidated image layer DiffIDs
Source: CVE Program / CVE List V5
Vulnerability 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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
完整性检查值验证不恰当
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
moby BuildKit 0 ~ 0.33.1 -

II. Public POCs for CVE-2026-93318

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-93318

请登录查看更多情报信息。

Other References for CVE-2026-93318 (2)

Same Patch Batch · moby · 2026-10-05 · 8 CVEs total

CVE-2026-93316 7.1 HIGH Starting daemon with --cdi-disabled flag can lead to panic on specific builds
CVE-2026-93322 6.9 MEDIUM Malformed MergeOp can crash the BuildKit daemon
CVE-2026-93323 6.8 MEDIUM Oversized Dockerfile or .dockerignore can exhaust buildkitd memory
CVE-2026-93320 6.0 MEDIUM BuildKit improperly handles special files in build snapshots
CVE-2026-93326 6.0 MEDIUM Crafted Git build source can bypass certain policy validation
CVE-2026-93317 5.9 MEDIUM Container blob cache can accept unverified content
CVE-2026-93319 5.7 MEDIUM A malicious frontend can cause a daemon panic

IV. Related Vulnerabilities

Same product: BuildKit
Same vendor: moby
Same weakness: CWE-354

V. Comments for CVE-2026-93318

No comments yet

Leave a comment