CVE-2026-55531: PraisonAI: Unauthenticated unbounded session accumulation in the PraisonAI MCP HTTP server (memory exhaustion; session TTL never enforced)

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-09-09
Weakness: CWE-400

Description

PraisonAI is a multi-agent teams system. Prior to praisonai 4.6.58, the MCP HTTP Stream mcp_post handler creates a new _sessions entry for every initialize request but does not call _cleanup_sessions or enforce a maximum. An unauthenticated caller can exhaust memory. The fix invokes cleanup and limits sessions through PRAISONAI_MCP_MAX_SESSIONS. This issue is fixed in version 4.6.58.

Affected products

MervinPraison PraisonAI: before 4.6.58

References

https://github.com/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1
https://github.com/MervinPraison/PraisonAI/releases/tag/v4.6.58
https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-wv94-5qcp-6m36
https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-wv94-5qcp-6m36

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