CVE-2026-51715
Unauthenticated removal of MAC filter rules on TOTOLINK T6 router
Is CVE-2026-51715 being exploited?
Not confirmed. CVE-2026-51715 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 0.35% probability of exploitation in the next 30 days.
How severe is CVE-2026-51715?
CVE-2026-51715 is rated Critical with a CVSS score of 9.8. 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-2026-51715?
Yes. A fix has been recorded for CVE-2026-51715. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-51715 affect?
CVE-2026-51715 affects TOTOLINK T6 (firmware 4.1.5cu.748_B20211015), TOTOLINK home/SMB routers with same CGI endpoint. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-51715?
Apply vendor firmware update and block WAN access to router management immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote attacker can delete MAC filter rules via crafted POST to /cgi-bin/cstecgi.cgi, disabling MAC-based access controls and enabling unauthorized devices.
Immediate action required