CVE-2026-126256 Memory corruption in FortiOS
A remote privileged attacker can send crafted packets to trigger an out-of-bounds read and execute code on FortiOS devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Harmful if only installed
- No
- Needs a specific call
- No
- Fix
- None listed
What is CVE-2026-126256?
CVE-2026-126256 is a high-severity memory corruption vulnerability in Fortinet FortiOS, published on 11 Nov 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A out-of-bounds read vulnerability in Fortinet FortiOS 8.0.0 through 8.0.1, FortiOS 7.6.0 through 7.6.7, FortiOS 7.4.0 through 7.4.12, FortiOS 7.2.0 through 7.2.13 may allow a remote privileged attacker to execute arbitrary code or command via crafted paquets.
Weakness: CWE-125
Which versions are affected by CVE-2026-126256?
An affected version is exposed as installed. No special setting or call is needed.
How do I fix CVE-2026-126256?
No fix has been published for CVE-2026-126256 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-2026-126256 being exploited?
There is no known exploitation of CVE-2026-126256 in the wild and no public exploit code.
Sources
Also known as GHSA-7j3m-m4x5-rfh7.