What is CVE-2025-67188?

CVE-2025-67188 is a critical-severity vulnerability in Totolink A950rg, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-02-03.

How severe is CVE-2025-67188?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Totolink A950rg

CVE-2025-67188

A buffer overflow vulnerability exists in TOTOLINK A950RG V4.1.2cu.5204_B20210112. The issue resides in the setRadvdCfg interface of the /lib/cste_modules/ipv6.so module. The function fails to properly validate the length of the user-controlled radvdinterfacename parameter, allowing remote attackers to trigger a stack buffer overflow.

Vulnerability class: Buffer Overflow

Published 2026-02-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (49.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.007 · change: +0.000

Affected products

Totolink A950rg
Totolink A950rg Firmware — versions 4.1.2cu.5204_b20210112

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

github.com/SunnyYANGyaya/cuicuishark-sheep-fishIOT/blob/main/ToTolink/A950RG/50… (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2025-67188?: CVE-2025-67188 is a critical-severity vulnerability in Totolink A950rg, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-02-03.
How severe is CVE-2025-67188?: Critical severity. CVSS v3 base score is 9.8 out of 10.