CVE-2026-43899

CRITICAL
INFO Priority: 0.04 BB Relevance: 69/100
Published: 2026-05-11 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Conf. Impact Integ. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Required
S: Changed
C: High
I: High
A: High

Description

DeepChat is an open-source artificial intelligence agent platform that unifies models, tools, and agents. Prior to v1.0.4-beta.1, An incomplete mitigation for CVE-2025-55733 leaves DeepChat vulnerable to an arbitrary protocol execution bypass (RCE). While the patch correctly restricted api.openExternal() inside the renderer's preload/index.ts script, it structurally neglected to sanitize native Electron pop-up window handlers. An attacker or a compromised AI endpoint returning a Markdown link can trigger a target="_blank" native window interception in tabPresenter.ts, which forwards the malicious URL directly to shell.openExternal(url) and completely bypasses the isValidExternalUrl security boundary. This vulnerability is fixed in v1.0.4-beta.1.

Weakness Classification (1)

Bug Bounty Relevance

69 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

9.6 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

EPSS — Exploitation Probability

0.40%
Raw Score 0.004010
Percentile 34.3%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00401
2026-10-28
0.00401

Intelligence Sources

nvd ref →