Skip to content
OpenAdvisories
Medium · 6.9 CVE-2026-55529 EUVD-2026-65496GHSA-wj6g-v78p-6fx3PYSEC-2026-3896

PraisonAI: Origin validation bypass in MCP HTTP Stream transport allows browser-mediated unauthenticated tool execution on local MCP server

Published Aug 25, 2026 · Updated Aug 27, 2026 · Assigned by GitHub_M

Description

PraisonAI is a multi-agent teams system. Prior to praisonai 4.6.58, the MCP HTTP Stream _validate_origin method accepts request_origin.startswith(allowed), so the attacker-controlled localhost.evil.example HTTP origin matches the localhost allowlist. Without an API key, a malicious webpage can submit tools/call requests to the local MCP server and execute exposed tools. This issue is fixed in version 4.6.58.

Affected products

VendorProductAffectedFixed
MervinPraison PraisonAI < 4.6.58 —

Affected packages

EcosystemPackageAffectedFixedRecord
PyPI praisonai < 4.6.58 4.6.58 GHSA-wj6g-v78p-6fx3

References