Local root escalation via writable linker cache
Published Jul 18, 2025 · Updated Jul 22, 2025
Incorrect permissions in Chainguard apko 0.27.0 through 0.29.4 allow local users to escalate privileges through generated images. The updateCache function creates /etc/ld.so.cache with os.Create, leaving mode 0666 rather than restricting writes to root. A low-privileged user inside an affected glibc-based image can rewrite the cache to load a malicious library from a controlled directory and execute code as root.
Summary
What happened
Incorrect permissions in Chainguard apko 0.27.0 through 0.29.4 allow local users to escalate privileges through generated images. The updateCache function creates /etc/ld.so.cache with os.Create, leaving mode 0666 rather than restricting writes to root. A low-privileged user inside an affected glibc-based image can rewrite the cache to load a malicious library from a controlled directory and execute code as root.
The record
- CVE
- CVE-2025-53945
- Published
- Jul 18, 2025
- Updated
- Jul 22, 2025
- Vendor
- Chainguard
- Product
- apko
- Classifications
- CWE-276, T1574.006
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 18, 2025CVE publishedPublication date reported by the CVE source.
- Jul 22, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 0.27.0, < 0.29.5
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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