Vulnerability · Published Nov 7, 2026 · Assigned by VulDB
CVE-2026-123960TOTOLINK CA300-PoE cstecgi.cgi setWanConfig buffer overflow
Critical 9.9
In plain English
A critical-severity buffer overflow in CA300-PoE from TOTOLINK. There are no confirmed reports of exploitation so far.
Severity (CVSS 3.1)9.9Critical
Exploit odds (30 days)–no EPSS score yet
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
A weakness has been identified in TOTOLINK CA300-PoE 6.2c.884. This affects the function setWanConfig of the file /cgi-bin/cstecgi.cgi. Executing a manipulation of the argument pppoeUser/priDns/secDns 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)
Weakness: CWE-120, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:C
References
- VDB-432023 | TOTOLINK CA300-PoE cstecgi.cgi setWanConfig buffer overflow vdb-entry, technical-description
- VDB-432023 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
- CVE-2026-123960 | CVE Analysis and Report third-party-advisory
- Submit #1033722 | TOTOLINK CA300-PoE CA300-PoE_Firmware V6.2c.884 Buffer Overflow third-party-advisory
- https://lavender-bicycle-a5a.notion.site/TOTOLINK-CA300-PoE-setWanConfig-3f953a41781f80ec86f3c2840cb5fc4b?source=copy_link exploit
- https://www.totolink.net/ product