Vulnerability · Published May 4, 2026 · Assigned by VulDB

CVE-2026-7748Totolink N300RH POST Request cstecgi.cgi setUpgradeFW buffer overflow

High 8.8

In plain English

A high-severity buffer overflow in N300RH from Totolink. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities).

Severity (CVSS 3.1)8.8High

Exploit odds (30 days)0.5%top 59.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

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.

Affected products (as reported)

Vendor	Product	Versions
Totolink	N300RH	3.2.4-B20220812

Weakness: CWE-120, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R

References

VDB-360923 | Totolink N300RH POST Request cstecgi.cgi setUpgradeFW buffer overflow vdb-entry, technical-description
VDB-360923 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
Submit #807202 | Totolink N300RH N300RH V3_Firmware V3.2.4-B20220812 Buffer Overflow third-party-advisory
https://lavender-bicycle-a5a.notion.site/TOTOLINK-N300RH-setUpgradeFW-34553a41781f80abb1d1c627d7ff4329?pvs=73 exploit, patch
https://www.totolink.net/ product