CVE-2025-59835 LangBot has a cross-directory file upload vulnerability, which could lead to system takeover
Authorized attackers can upload arbitrary files to system directories via the file upload interface, potentially leading to system takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-59835?
CVE-2025-59835 is a high-severity vulnerability in langbot-app LangBot, published on 2 Oct 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
LangBot is a global IM bot platform designed for LLMs. In versions 4.1.0 up to but not including 4.3.5, authorized attackers can exploit the /api/v1/files/documents interface to perform arbitrary file uploads. Since this interface does not strictly restrict the storage directory of files on the server, it is possible to upload dangerous files to specific system directories. This is fixed in version 4.3.5.
Which versions are affected by CVE-2025-59835?
How do I fix CVE-2025-59835?
No fix has been published for CVE-2025-59835 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-59835 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-59835 exists.
Sources
Also known as GHSA-7j3j-qj83-9qv4.