Root-owned file creation via log-directory symlink attack
Published May 5, 2021 · Updated Sep 17, 2024
Incorrect permissions in packaged CUPS on affected SUSE and openSUSE releases allow local users in the lp group to create root-owned files. The lp-owned /var/log/cups directory permits a controlled symlink to redirect root CUPS log-file creation, producing a root-owned mode-0644 file without attacker-controlled content. Membership in the lp group and local access are required; integrity impact is limited to file creation rather than arbitrary content writes.
Summary
What happened
Incorrect permissions in packaged CUPS on affected SUSE and openSUSE releases allow local users in the lp group to create root-owned files. The lp-owned /var/log/cups directory permits a controlled symlink to redirect root CUPS log-file creation, producing a root-owned mode-0644 file without attacker-controlled content. Membership in the lp group and local access are required; integrity impact is limited to file creation rather than arbitrary content writes.
The record
- CVE
- CVE-2021-25317
- Published
- May 5, 2021
- Updated
- Sep 17, 2024
- Vendor
- OpenSUSE
- Product
- openSUSE Leap
- Classifications
- CWE-276, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 5, 2021CVE publishedPublication date reported by the CVE source.
- Sep 17, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=cups <2.2.7
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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