Is CVE-2026-43899 actively exploited?

No active exploitation of CVE-2026-43899 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-43899 be exploited remotely?

Yes. CVE-2026-43899 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-43899?

CVE-2026-43899 has a CVSS score of 9.6 (CRITICAL).

HOME VULNERABILITIESCVE-2026-43899

CRITICAL

CVE-2026-43899

CWE-20Published: May 11, 2026· Updated: May 12, 2026

9.6

CVSS v3.1

EPSS:0.07%probability of exploitation in 30 daysPercentile:21.9th

Official 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.

NVD Source

Technical Analysis

CVE-2026-43899 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.6.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.