Stored XSS via unsafe WebIDE mediator URL
Published Aug 1, 2023 · Updated Aug 14, 2026
Stored XSS in GitLab allows remote authenticated users to execute JavaScript in another user's session through a crafted WebIDE link. The SET_HREF mediator accepts an attacker-controlled href, resolves it as a URL, and assigns it to the parent window without rejecting the javascript scheme. Exploitation requires project access, a victim Ctrl/Cmd-clicking the Markdown link, and a self-managed instance without strict CSP; code runs with the victim's session access.
Summary
What happened
Stored XSS in GitLab allows remote authenticated users to execute JavaScript in another user's session through a crafted WebIDE link. The SET_HREF mediator accepts an attacker-controlled href, resolves it as a URL, and assigns it to the parent window without rejecting the javascript scheme. Exploitation requires project access, a victim Ctrl/Cmd-clicking the Markdown link, and a self-managed instance without strict CSP; code runs with the victim's session access.
The record
- CVE
- CVE-2023-2164
- Published
- Aug 1, 2023
- Updated
- Aug 14, 2026
- Vendor
- GitLab
- Product
- GitLab
- Classifications
- CWE-79, T1204.001
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 1, 2023CVE publishedPublication date reported by the CVE source.
- Aug 14, 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=15.9 <16.0.8
- Affected versionversion=16.1.0 <16.1.3
- Affected versionversion=16.2.0 <16.2.2
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.
Weakness, pattern, technique
Public exploit references
- GitLab WebIDE SET_HREF proof of conceptproof 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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