TI-2026-29071 Aliases CVE-2026-40289 GHSA-8x8f-54wf-vv92

PraisonAI Browser Server allows unauthenticated WebSocket clients to hijack connected extension sessions

HIGH 80CWE-306Published 2026-04-14 · Updated 2026-04-14

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: High · High · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-306.

Summary

PraisonAI is a multi-agent teams system. In versions below 4.5.139 of PraisonAI and 1.5.140 of praisonaiagents, the browser bridge (praisonai browser start) is vulnerable to unauthenticated remote session hijacking due to missing authentication and a bypassable origin check on its /ws WebSocket endpoint. The server binds to 0.0.0.0 by default and only validates the Origin header when one is present, meaning any non-browser client that omits the header is accepted without restriction. An unauthenticated network attacker can connect, send a start_session message, and the server will route it to the first idle browser-extension WebSocket (effectively hijacking that session) and then broadcast all resulting automation actions and outputs back to the attacker. This enables unauthorized remote control of connected browser automation sessions, leakage of sensitive page context and automation results, and misuse of model-backed browser actions in any environment where the bridge is network-reachable. This issue has been fixed in versions 4.5.139 of PraisonAI and 1.5.140 of praisonaiagents.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00421 36th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed PraisonAI (MervinPraison): 4.5.139praisonaiagents (MervinPraison): 1.5.140+2 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
MervinPraison	PraisonAI	before 4.5.139	4.5.139	Patch available	CNA
MervinPraison	praisonaiagents	before 1.5.140	1.5.140	Patch available	CNA
—	praisonaiagents (PyPI)	before 1.5.140	1.5.140	Patch available	GHSA-8x8f-54wf-vv92
—	PraisonAI (PyPI)	before 4.5.139	4.5.139	Patch available	GHSA-8x8f-54wf-vv92

PraisonAI VendorMervinPraison Affected before 4.5.139 Fixed in 4.5.139 Patch available CNA
praisonaiagents VendorMervinPraison Affected before 1.5.140 Fixed in 1.5.140 Patch available CNA
praisonaiagents (PyPI) Vendor— Affected before 1.5.140 Fixed in 1.5.140 Patch available GHSA-8x8f-54wf-vv92
PraisonAI (PyPI) Vendor— Affected before 4.5.139 Fixed in 4.5.139 Patch available GHSA-8x8f-54wf-vv92

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:praison:praisonai::::::::	before 4.5.139	Vulnerable	MervinPraison
cpe:2.3:a:praison:praisonaiagents::::::python::*	before 1.5.140	Vulnerable	MervinPraison

cpe:2.3:a:praison:praisonai:*:*:*:*:*:*:*:* Versions before 4.5.139 Vulnerable ·MervinPraison
cpe:2.3:a:praison:praisonaiagents:*:*:*:*:*:python:*:* Versions before 1.5.140 Vulnerable ·MervinPraison

Remediation

Fix · CNA PraisonAI (MervinPraison) Fixed in 4.5.139
Fix · CNA praisonaiagents (MervinPraison) Fixed in 1.5.140
Fix · GHSA-8x8f-54wf-vv92 praisonaiagents (PyPI) Fixed in 1.5.140 Advisory →
Fix · GHSA-8x8f-54wf-vv92 PraisonAI (PyPI) Fixed in 4.5.139 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-40289
2026-10-03 Alias added: GHSA-8x8f-54wf-vv92

References

Exploit 1

https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-8x8f-54wf-vv92

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-40289

Other 2

TI-2026-30083 Incomplete fix for CVE-2026-34935: Command Injection in MervinPraison/PraisonAI CVSS 3.1CRITICAL 9.8
TI-2026-29070 PraisonAI: Critical RCE via `type: job` workflow YAML CVSS 3.1CRITICAL 9.8
TI-2026-28940 PraisonAI has Server-Side Request Forgery via Unvalidated webhook_url in Jobs API CVSS 3.1CRITICAL 10.0
TI-2026-28768 PraisonAI Affected by Remote Code Execution via YAML Deserialization in Agent Definition Loading CVSS 3.1CRITICAL 9.8
TI-2026-27159 PraisonAI: OS Command Injection in MCPHandler.parse_mcp_command() CVSS 3.1CRITICAL 9.8
TI-2026-27158 PraisonAI: Second-Order SQL Injection in `get_all_user_threads` CVSS 3.1CRITICAL 9.8

See all 42 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences