CVE-2026-42021 Multiple stack-based buffer overflow vulnerabilities exist in the boa formIpv6Setup static network configuration functionality of Totolink X

Critical 9.1 Published 20 Oct 2026 Updated 23 Oct 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-42021?

CVE-2026-42021 is a critical vulnerability in Totolink, published on 20 Oct 2026.

Official description

Multiple stack-based buffer overflow vulnerabilities exist in the boa formIpv6Setup static network configuration functionality of Totolink X2000R 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 concerns the static_dns1 parameter.

Weakness: CWE-121

Which versions are affected by CVE-2026-42021?

How do I fix CVE-2026-42021?

No fix has been published for CVE-2026-42021 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-42021 being exploited?

There is no known exploitation of CVE-2026-42021 in the wild and no public exploit code.

Sources

Also known as GHSA-9hw7-42mj-hjfc.