Protected-branch writes via retained deploy-key authorization
Published Sep 29, 2023 · Updated May 17, 2026
Incorrect authorization in GitLab before 16.2.7, 16.3 before 16.3.5, and 16.4 before 16.4.1 lets remote authenticated users write protected branches. Removal from a top-level group failed to revoke protected-branch allowances derived from inherited membership, while public-project deploy-key authorization accepted the stale access. Exploitation requires prior maintainer access, a write-enabled deploy key, and a public project; the retained key permits repository changes after membership ends.
Summary
What happened
Incorrect authorization in GitLab before 16.2.7, 16.3 before 16.3.5, and 16.4 before 16.4.1 lets remote authenticated users write protected branches. Removal from a top-level group failed to revoke protected-branch allowances derived from inherited membership, while public-project deploy-key authorization accepted the stale access. Exploitation requires prior maintainer access, a write-enabled deploy key, and a public project; the retained key permits repository changes after membership ends.
The record
- CVE
- CVE-2023-5198
- Published
- Sep 29, 2023
- Updated
- May 17, 2026
- Vendor
- GitLab
- Product
- GitLab
- Classifications
- CWE-863, T1098
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 29, 2023CVE publishedPublication date reported by the CVE source.
- May 17, 2026Record 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 <=16.2.7
- Affected versionversion=16.3 <16.3.5
- Affected versionversion=16.4 <16.4.1
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
- Protected-branch deploy-key reproductionproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
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