CVE-2024-23652: BuildKit vulnerable to possible host system access from mount stub cleaner

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 2.5%, percentile 84: FIRST’s model estimates a 2.5% chance of exploitation activity in the next 30 days, higher than 84% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes github.com/moby/buildkit (Go) < 0.12.5, fixed in 0.12.5. Check your lockfile, including transitive dependencies.
• Editorial verdict: Patch this week. Leaky Vessels: runc Container Escape (CVE-2024-21626) — A real container escape, but it needs you to run an attacker-controlled image or a crafted exec; patch runc everywhere promptly, urgently where untrusted images or multi-tenant builds run.

What it is

BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. A malicious BuildKit frontend or Dockerfile using RUN --mount could trick the feature that removes empty files created for the mountpoints into removing a file outside the container, from the host system. The issue has been fixed in v0.12.5. Workarounds include avoiding using BuildKit frontends from an untrusted source or building an untrusted Dockerfile containing RUN --mount feature.

From the GitHub advisory

Impact A malicious BuildKit frontend or Dockerfile using RUN --mount could trick the feature that removes empty files created for the mountpoints into removing a file outside the container, from the host system.

Patches The issue has been fixed in v0.12.5

Workarounds Avoid using BuildKit frontend from an untrusted source or building an untrusted Dockerfile containing RUN --mount feature.

References

Weakness type: CWE-22.

Product: github.com/moby/buildkit (Go) · Assigned by: GitHub_M · Published: 2024-01-31

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 2.46% probability of exploitation activity in the next 30 days; percentile 84.

Timeline

• 2024-01-31 — CVE record published by GitHub_M
• 2024-01-31 — GitHub-reviewed advisory GHSA-4v98-7qmw-rqr8 published (critical)
• 2024-01-31 — erroneo.us brief: Leaky Vessels: runc Container Escape (CVE-2024-21626)
• 2025-06-17 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-4v98-7qmw-rqr8 github.com
2. CVE.org record CVE-2024-23652 cve.org
3. NVD entry CVE-2024-23652 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com

Critical Go advisories · Today’s Security Digest