Buffer overflow in Totolink A3300r

CVE-2025-12240

A security vulnerability has been detected in TOTOLINK A3300R 17.0.0cu.557_B20221024. This affects the function setDmzCfg of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument ip leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed publicly and may be used.

Vulnerability class: Buffer Overflow

EPSS: 0.008 (51.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-12240?
CVE-2025-12240 is a high-severity vulnerability in Totolink A3300r, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2025-10-27.
How severe is CVE-2025-12240?
High severity. CVSS v3 base score is 8.8 out of 10.