Vulnerability in Unclecode Crawl4ai
CVE-2026-115508
Crawl4AI 0.7.0 before 0.9.5 contains an inefficient regular expression complexity vulnerability in the Docker API server that allows authenticated API clients to supply unbounded regular expressions in /crawl request bodies. Attackers can submit catastrophic-backtracking patterns via RegexExtractionStrategy.custom, RegexChunking.patterns or JsonCss, JsonXPath and JsonLxml schema regex fields against a crafted page to freeze the entire server, including /health.
Vulnerability class: ReDoS (Regular Expression Denial of Service)
Published .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/unclecode/crawl4ai/security/advisories/GHSA-j843-8p47-rhxp (vendor-advisory)
- github.com/unclecode/crawl4ai/commit/8aea2006e2cdb96a185e50b20633fc323dff6429 (patch)
- github.com/unclecode/crawl4ai/releases/tag/v0.9.5 (release-notes)
- github.com/unclecode/crawl4ai (product)
- www.vulncheck.com/advisories/crawl4ai-0.7.0-before-0.9.5-redos-via-crawl-regex-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-115508?
- CVE-2026-115508 is a medium-severity vulnerability in Unclecode Crawl4ai, classified under Inefficient Regular Expression Complexity. CVSS score: 6.5/10. Published 2026-10-22.
- How severe is CVE-2026-115508?
- Medium severity. CVSS v3 base score is 6.5 out of 10.