Security Digest · Vulnerability record
CVE-2024-23651: BuildKit possible race condition with accessing subpaths from cache mounts
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner.
CVSS 8.7 High EPSS 0.9% · p60 Patch this week
Should you act?
Normal patch cycle
No exploitation signal; fix it in your next routine update if you are affected. 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 0.9%, percentile 60: FIRST’s model estimates a 0.9% chance of exploitation activity in the next 30 days, higher than 60% of all scored CVEs (moderate). 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.
- 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. Two malicious build steps running in parallel sharing the same cache mounts with subpaths could cause a race condition that can lead to files from the host system being accessible to the build container. The issue has been fixed in v0.12.5. Workarounds include, avoiding using BuildKit frontend from an untrusted source or building an untrusted Dockerfile containing cache mounts with --mount=type=cache,source=... options.
Weakness type: CWE-362.
Product: moby buildkit · Assigned by: GitHub_M · Published: 2024-01-31
Affected and fixed versions
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| moby | buildkit | < 0.12.5 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 8.7 High | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
- Attack vector: network (remotely reachable)
- Attack complexity: high (needs special conditions)
- 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 no, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.91% probability of exploitation activity in the next 30 days; percentile 60.
Timeline
- — CVE record published by GitHub_M
- — erroneo.us brief: Leaky Vessels: runc Container Escape (CVE-2024-21626)
- — 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
- CVE.org record CVE-2024-23651 cve.org
- NVD entry CVE-2024-23651 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com