CVE-2026-7748 Totolink N300RH POST Request cstecgi.cgi setUpgradeFW buffer overflow
Remote attackers can trigger a buffer overflow in the firmware upgrade handler via a manipulated FileName argument, potentially leading to code execution or service disruption.
- 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-2026-7748?
CVE-2026-7748 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 weakness has been identified in Totolink N300RH 3.2.4-B20220812. Affected by this issue is the function setUpgradeFW of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. Executing a manipulation of the argument FileName can lead to buffer overflow. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks.
Which versions are affected by CVE-2026-7748?
How do I fix CVE-2026-7748?
No fix has been published for CVE-2026-7748 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-2026-7748 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-7748 exists.
Sources
Also known as GHSA-586v-9hf5-74vw.