CVE-2026-22320 Stack-Based Buffer Overflow in TFTP File-Transfer Command Handling over CLI
A low-privileged attacker can cause a denial of service by triggering a stack-based buffer overflow in the CLI's TFTP command handling.
- 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-2026-22320?
CVE-2026-22320 is a medium-severity memory corruption vulnerability in Phoenix Contact FL NAT 2008, published on 18 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A stack-based buffer overflow in the CLI's TFTP file‑transfer command handling allows a low-privileged attacker with Telnet/SSH access to trigger memory corruption by supplying unexpected or oversized filename input. Exploitation results in the corruption of the internal buffer, causing the CLI and web dashboard to become unavailable and leading to a denial of service.
Weakness: CWE-121
Which versions are affected by CVE-2026-22320?
How do I fix CVE-2026-22320?
No fix has been published for CVE-2026-22320 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-2026-22320 being exploited?
There is no known exploitation of CVE-2026-22320 in the wild and no public exploit code.
Sources
Also known as GHSA-22m2-mv56-5hwq.