Buffer overflow in Totolink

CVE-2026-9659

Multiple exploitable stack-based buffer overflow vulnerabilities exist in the boa formFilter functionality of X2000R (version(s): TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327). A specially crafted HTTP request can lead to arbitrary code execution. An attacker can make an authenticated HTTP request to trigger these vulnerabilities. This vulnerability deals with the vpnUser parameter.

Vulnerability class: Buffer Overflow

Published .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

  • Totolink — versions TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-9659?
CVE-2026-9659 is a critical-severity vulnerability in Totolink, classified under Stack-based Buffer Overflow. CVSS score: 9.1/10. Published 2026-10-20.
How severe is CVE-2026-9659?
Critical severity. CVSS v3 base score is 9.1 out of 10.