# CVE-2026-93317: Container blob cache can accept unverified content

> An attacker can poison the container blob cache with unverified content, compromising build integrity for subsequent users.

- **Severity:** Medium 5.9 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 5 Oct 2026
- **Updated:** 5 Oct 2026
- **Also known as:** GHSA-p3rc-w3hc-pqvv, UBUNTU-CVE-2026-93317

## What is CVE-2026-93317?

CVE-2026-93317 is a medium-severity vulnerability in moby BuildKit, published on 5 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

An unauthenticated attacker controlling a registry or OCI-layout blob source could provide blob contents that did not match the claimed digest. The resulting snapshot could be cached under that digest and reused by a later victim build, compromising build-input integrity.

Weakness: CWE-354 (Improper Validation of Integrity Check Value)

## Which versions are affected by CVE-2026-93317?


## How do I fix CVE-2026-93317?

No fix has been published for CVE-2026-93317 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-93317 being exploited?

There is no known exploitation of CVE-2026-93317 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93317 and fix it if it is affected.

What it is: CVE-2026-93317 is a medium-severity vulnerability in moby BuildKit, published on 5 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-93317 in the wild and no public exploit code.

Affected product: moby BuildKit. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-93317/ (Markdown: https://insights.sbomify.com/CVE-2026-93317/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93317
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93317
- OSV: https://osv.dev/vulnerability/CVE-2026-93317

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93317/
Summaries are generated and may contain mistakes; the official description above is the record.