What’s Vulnerable › Vulnerabilities
CVE-2026-34939: PraisonAI: ReDoS via Unvalidated User-Controlled Regex in MCPToolIndex.search_tools()
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2026-04-03 · updated 2026-07-24
- Weakness: CWE-1333
Description
PraisonAI is a multi-agent teams system. Prior to version 4.5.90, MCPToolIndex.search_tools() compiles a caller-supplied string directly as a Python regular expression with no validation, sanitization, or timeout. A crafted regex causes catastrophic backtracking in the re engine, blocking the Python thread for hundreds of seconds and causing a complete service outage. This issue has been patched in version 4.5.90.
Affected products
- MervinPraison PraisonAI: before 4.5.90 — fixed in 4.5.90
How to fix
Upgrade to a fixed version: MervinPraison PraisonAI 4.5.90. Check the vendor advisory for mitigations.
References
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