CVE-2026-55529

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

Published Aug 25, 2026 CVSS 3.1 · 6.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-wj6g-v78p-6fx3 PraisonAI has an origin validation bypass in MCP HTTP Stream transport that allows browser-mediated unauthenticated tool execution on local MCP server
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Mervinpraison
Mervinpraison praisonai
Vendors & Products Mervinpraison
Mervinpraison praisonai
Type Values Removed Values Added
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.
Title PraisonAI: Origin validation bypass in MCP HTTP Stream transport allows browser-mediated unauthenticated tool execution on local MCP server
Weaknesses CWE-306
CWE-346
References
Metrics cvssV3_1

{'score': 6.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 27, 2026, 3:15 PM
Reserved
Jun 16, 2026, 11:01 PM
Status
Deferred
Published
Aug 25, 2026, 3:16 PM
Modified
Sep 9, 2026, 9:07 PM