CVE-2026-7749 Totolink N300RH POST Request cstecgi.cgi setWanConfig buffer overflow
Remote attackers can trigger a buffer overflow in the Totolink N300RH router's WAN configuration handler, potentially leading to arbitrary code execution.
- 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-2026-7749?
CVE-2026-7749 is a high-severity memory corruption vulnerability in Totolink N300RH, published on 4 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A security vulnerability has been detected in Totolink N300RH 3.2.4-B20220812. This affects the function setWanConfig of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. The manipulation of the argument priDns leads to buffer overflow. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used.
Which versions are affected by CVE-2026-7749?
How do I fix CVE-2026-7749?
No fix has been published for CVE-2026-7749 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-2026-7749 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-7749 exists.
Sources
Also known as GHSA-9639-rx99-qmgv.