Skip to content
Networks

CVE-2026-51701

9.1
Critical
EPSS 0.36%Patch availableSep 1, 2026

Unauthenticated remote modification of MAC filter rules on TOTOLINK T6 routers.

common questions

Is CVE-2026-51701 being exploited?

Not confirmed. CVE-2026-51701 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.36% probability of exploitation in the next 30 days.

How severe is CVE-2026-51701?

CVE-2026-51701 is rated Critical with a CVSS score of 9.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.

Is there a patch for CVE-2026-51701?

Yes. A fix has been recorded for CVE-2026-51701. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2026-51701 affect?

CVE-2026-51701 affects TOTOLINK T6 firmware 4.1.5cu.748_B20211015 (setMacFilterRules via /cgi-bin/cstecgi.cgi). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

What should I do about CVE-2026-51701?

Apply vendor firmware update immediately and restrict remote admin access.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

executive summary
technical analysis
affected
TOTOLINK T6 firmware 4.1.5cu.748_B20211015 (setMacFilterRules via /cgi-bin/cstecgi.cgi)
impact

Unauthenticated attacker can POST to /cgi-bin/cstecgi.cgi setMacFilterRules to change MAC filters, bypass/alter access controls, enable persistent unauthorized access or lock out devices.

action required

Immediate action required

how to fix
Remediation steps are tailored for users whose stack is affected. Add this technology to your stack to see the fix checklist.
references
get alerted

Track only the vulnerabilities that affect your infrastructure.

start for free