CVE-2025-8760 INSTAR 2K+/4K fcgi_server base64_decode buffer overflow
Remote attackers can trigger a buffer overflow in the fcgi_server base64_decode function via the Authorization header, potentially leading to code execution or service disruption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-8760?
CVE-2025-8760 is a critical memory corruption vulnerability in INSTAR 2K+, published on 13 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability was identified in INSTAR 2K+ and 4K 3.11.1 Build 1124. This affects the function base64_decode of the component fcgi_server. The manipulation of the argument Authorization leads to buffer overflow. It is possible to initiate the attack remotely.
Which versions are affected by CVE-2025-8760?
How do I fix CVE-2025-8760?
No fix has been published for CVE-2025-8760 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-8760 being exploited?
There is no known exploitation of CVE-2025-8760 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-4jm8-qw96-rm2j.