Bake filesystem path entitlements approval can be skipped for path using basename prefix
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 0.38.1
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 0.38.1.
- Exploitation?/40Exploitation: unknown (data gap). No CISA SSVC exploitation rating yet
- Exposure?/25Exposure: unknown (data gap). No advisory context yet
- Reach17/20Affects Docker (a widely deployed server, runtime, framework or database)
- Severity1.8/10CVSS 1.8
- No patch0/5No signal
What would change the score
- Would score about 74 if added to CISA KEV
- Would score about 69 if CISA's SSVC rates exploitation active
- Would score about 41 if advisories confirm default setups are exposed
CVE-2026-121542 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 1.8 (low) and affects Docker Buildx; fixed in 0.38.1.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 19/100 · provisional
- Fix
- Fixed in 0.38.1
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Docker Buildx, the Docker CLI plugin for building container images, is affected when it processes Bake definitions. An untrusted Bake definition could read local files that should have required explicit filesystem read approval, potentially exposing sensitive files to the person building.
Read the original description
In Docker Buildx versions v0.19.0 through v0.38.0, an untrusted Bake definition may expose files accessible to the Buildx client without the expected fs.read approval. Under certain conditions, paths under the same parent directory as the current working directory whose names use the working directory's basename as a prefix can skip the filesystem entitlement check. Exploitation requires specific matching filenames next to the current project directory. Users who run untrusted Bake definitions may be affected. The issue is fixed in v0.38.1.
What to do
Upgrade to a fixed version: 0.38.1.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- Docker Docker Buildx
From 0.19.0 · fixed in 0.38.1
Evidence 1
- Advisory
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-121542
Is CVE-2026-121542 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
Which versions are affected by CVE-2026-121542?
Docker Buildx: from 0.19.0 before 0.38.1.Source: cve.now feed data
How do I fix CVE-2026-121542?
Upgrade to a fixed version: 0.38.1.Source: cve.now feed data