How do I check whether I am affected by CVE-2026-42022?

Open the router admin page, go to System/Status and read the firmware version. TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327 is confirmed vulnerable. Other builds were not tested, so treat them as unknown. To check WAN exposure, turn off remote management in the admin settings, or scan your public IP for the web admin port (80, or 8080 if you changed it) from outside your network.

What is the fix for CVE-2026-42022?

No fixed firmware has been published as far as the sources show (unknown). Mitigation: disable WAN/remote web management, restrict the admin UI to a trusted LAN, change the default admin password, and turn off IPv6 static configuration if you do not use it. Watch totolink.net/X2000R downloads for a new build.

Who is not affected by CVE-2026-42022?

Not affected if: admin-not-exposed, auth-required, no-admin-credentials-for-attacker, no-web-admin-exposure.

Live › vulnerability › CVE-2026-42022

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critical9.1Infrastructure

TOTOLINK X2000R router: stack overflow in IPv6 setup lets attacker run code

Stack-based buffer overflow (CWE-121) in the boa web server's formIpv6Setup handler on the TOTOLINK X2000R. The static_dns2 POST parameter is copied to the stack with no length check. An authenticated attacker on the admin interface can send one HTTP request and run code on the router. Talos reproduced it on firmware B20250421.1327 and shows a controlled PC. Talos rates it 9.1 because it needs a login, but the router's default or weak credentials make that bar low.

Summary written from the sources below. Check the originals before acting.

CVSS 3.x

9.1

critical

scored by [email protected]

known so far5 of 6

missing: exploitation

First public: Oct 20, 2026 UTC
Last modified: Oct 23, 2026
Status: open
Known exploitation: None reported
Public exploit: None on GitHub
EPSS: not scored

First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.

Why it is critical, and not just CVSS

Likelihood → · Impact ↓

critical

high

medium

high

medium

low

medium

low

Exploited: No reports yet.
Needs login: Yes.
Needs a special setup: Not known from the sources.
Reachable from: network.
Worst case: Code runs on the router with full device control.
CVSS said: 9.1. The facts above say medium; we keep the sources' critical until an analyst looks.

Who is affected

1 product

Know the next one before it finds you.

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Live › vulnerability › CVE-2026-42022

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critical9.1Infrastructure

TOTOLINK X2000R router: stack overflow in IPv6 setup lets attacker run code

Summary written from the sources below. Check the originals before acting.

CVSS 3.x

9.1

critical

scored by [email protected]

known so far5 of 6

missing: exploitation

First public: Oct 20, 2026 UTC
Last modified: Oct 23, 2026
Status: open
Known exploitation: None reported
Public exploit: None on GitHub
EPSS: not scored

First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.

Why it is critical, and not just CVSS

Likelihood → · Impact ↓

critical

high

medium

high

medium

low

medium

low

Exploited: No reports yet.
Needs login: Yes.
Needs a special setup: Not known from the sources.
Reachable from: network.
Worst case: Code runs on the router with full device control.
CVSS said: 9.1. The facts above say medium; we keep the sources' critical until an analyst looks.

Who is affected

1 product

Know the next one before it finds you.

Add to Slack

TOTOLINK X2000R router: stack overflow in IPv6 setup lets attacker run code

Why it is critical, and not just CVSS

Who is affected

Know the next one before it finds you.

TOTOLINK X2000R router: stack overflow in IPv6 setup lets attacker run code

Why it is critical, and not just CVSS

Who is affected

Know the next one before it finds you.

How to check

The fix

Who had it, and when

What the sources say, verbatim

Sources