Service interruption via EpicReferenceFilter regex backtracking
Published Jul 13, 2023 · Updated Oct 30, 2024
Regular expression denial of service in GitLab CE/EE affected releases allows remote attackers to interrupt service through Markdown previews. The preview_markdown endpoint sends crafted Markdown through EpicReferenceFilter, whose inefficient regular-expression matching consumes excessive CPU. No authentication or user interaction is required, and sustained requests can make the instance unresponsive without disclosing or changing data.
Summary
What happened
Regular expression denial of service in GitLab CE/EE affected releases allows remote attackers to interrupt service through Markdown previews. The preview_markdown endpoint sends crafted Markdown through EpicReferenceFilter, whose inefficient regular-expression matching consumes excessive CPU. No authentication or user interaction is required, and sustained requests can make the instance unresponsive without disclosing or changing data.
The record
- CVE
- CVE-2023-3424
- Published
- Jul 13, 2023
- Updated
- Oct 30, 2024
- Vendor
- GitLab
- Product
- GitLab
- Classifications
- CWE-1333, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 13, 2023CVE publishedPublication date reported by the CVE source.
- Oct 30, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.3 <15.11.10
- Affected versionversion=16.0 <16.0.6
- Affected versionversion=16.1 <16.1.1
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.
Weakness, pattern, technique
Public exploit references
- HackerOne proof-of-concept reportproof of concept · unverified
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Technologies
Your stack
See the directory against your own environment.
Your stack
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