CVE-2026-36607

CVE-2026-36607 is a high-severity vulnerability with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.

Key facts

Description

Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 allows unauthenticated brute-force attacks via the TDDP password change endpoint (code=10), which lacks the rate limiting applied to the login endpoint (code=7). An attacker on the adjacent network can attempt unlimited passwords without triggering account lockout.

Frequently asked questions

What is CVE-2026-36607?
Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 allows unauthenticated brute-force attacks via the TDDP password change endpoint (code=10), which lacks the rate limiting applied to the login endpoint (code=7). An attacker on the adjacent network can attempt unlimited passwords without triggering account lockout.
How severe is CVE-2026-36607?
CVE-2026-36607 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-36607 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-36607?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-36607 have an EU (EUVD) identifier?
Yes. CVE-2026-36607 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34146.
When was CVE-2026-36607 published?
CVE-2026-36607 was published on 2026-06-03 and last updated on 2026-06-17.

References

Other CWE-307 (Improper Restriction of Excessive Authentication Attempts) vulnerabilities

Browse all CWE-307 (Improper Restriction of Excessive Authentication Attempts) vulnerabilities →