6.9
MEDIUM CVSS 3.1
CVE-2026-55529
PraisonAI: Origin validation bypass in MCP HTTP Stream transport allows browser-mediated unauthenticated tool execution on local MCP server
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.

INFO

Published Date :

Aug. 25, 2026, 3:16 p.m.

Last Modified :

Aug. 25, 2026, 3:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55529 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update PraisonAI to version 4.6.58 or later to fix the origin validation vulnerability.
  • Update PraisonAI to version 4.6.58.
  • Ensure proper origin validation is configured.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-55529.

URL Resource
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-wj6g-v78p-6fx3
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55529 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-55529 weaknesses.

CAPEC-12: Choosing Message Identifier Choosing Message Identifier CAPEC-36: Using Unpublished Interfaces or Functionality Using Unpublished Interfaces or Functionality CAPEC-62: Cross Site Request Forgery Cross Site Request Forgery CAPEC-166: Force the System to Reset Values Force the System to Reset Values CAPEC-216: Communication Channel Manipulation Communication Channel Manipulation CAPEC-21: Exploitation of Trusted Identifiers Exploitation of Trusted Identifiers CAPEC-59: Session Credential Falsification through Prediction Session Credential Falsification through Prediction CAPEC-60: Reusing Session IDs (aka Session Replay) Reusing Session IDs (aka Session Replay) CAPEC-75: Manipulating Writeable Configuration Files Manipulating Writeable Configuration Files CAPEC-76: Manipulating Web Input to File System Calls Manipulating Web Input to File System Calls CAPEC-89: Pharming Pharming CAPEC-111: JSON Hijacking (aka JavaScript Hijacking) JSON Hijacking (aka JavaScript Hijacking) CAPEC-141: Cache Poisoning Cache Poisoning CAPEC-142: DNS Cache Poisoning DNS Cache Poisoning CAPEC-160: Exploit Script-Based APIs Exploit Script-Based APIs CAPEC-384: Application API Message Manipulation via Man-in-the-Middle Application API Message Manipulation via Man-in-the-Middle CAPEC-385: Transaction or Event Tampering via Application API Manipulation Transaction or Event Tampering via Application API Manipulation CAPEC-386: Application API Navigation Remapping Application API Navigation Remapping CAPEC-387: Navigation Remapping To Propagate Malicious Content Navigation Remapping To Propagate Malicious Content CAPEC-388: Application API Button Hijacking Application API Button Hijacking CAPEC-510: SaaS User Request Forgery SaaS User Request Forgery

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55529 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55529 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'MervinPraison', 'product': 'PraisonAI', 'versions': [{'status': 'affected', 'version': '< 4.6.58'}]}]
    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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N
    Added CWE CWE-346
    Added CWE CWE-306
    Added Reference https://github.com/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1
    Added Reference https://github.com/MervinPraison/PraisonAI/releases/tag/v4.6.58
    Added Reference https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-wj6g-v78p-6fx3
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.