CVE-2026-55529

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

MEDIUM
6.9
CVSS Score
Published: August 25, 2026 at 02:26 PM UTC
Updated: September 9, 2026 at 09:27 PM UTC
1 product affected across 1 vendorPraisonAI

Using PraisonAI by MervinPraison?

Get instant alerts when new vulnerabilities affect PraisonAI - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.9
Exploit prediction
EPSS 0.2%
SSVC
PoC

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.6.58
Affected range stops below 4.6.58, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.9MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
HIGH
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-306CWE-346

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card