CVE-2026-34939: MervinPraison PraisonAI · ReDoS
Affects MervinPraison PraisonAISource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 4.5.90 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 34% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.5.90
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 3 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade PraisonAI and mervinpraison/PraisonAI to 4.5.90.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MervinPraisonPraisonAI | Affected
| Fixed in
|
GitHubmervinpraison/PraisonAIpkg:github/mervinpraison/PraisonAIOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
This vulnerability is patched in PraisonAI version 4.5.90. Users should upgrade to version 4.5.90 or later to remediate the issue. Since PraisonAI is not a cloud service, remediation requires applying the vendor's patch. Patch status is confirmed by the version update note; no additional vendor advisory is available. Until upgraded, avoid processing untrusted input as regular expressions in MCPToolIndex.search_tools().
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.