CVE-2026-43899 Code injection in deepchat
Attackers can execute arbitrary code by bypassing URL validation in native window handlers via malicious Markdown links in DeepChat.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-43899?
CVE-2026-43899 is a critical code injection vulnerability in ThinkInAIXYZ deepchat, published on 11 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
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.
Weakness: CWE-20
Which versions are affected by CVE-2026-43899?
How do I fix CVE-2026-43899?
No fix has been published for CVE-2026-43899 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-43899 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43899 exists.
Sources
Also known as GHSA-cp8j-jx7q-7r5f.