How severe is CVE-2026-36604?

CVE-2026-36604 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-36604 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-36604?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-36604 have an EU (EUVD) identifier?

Yes. CVE-2026-36604 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34143.

When was CVE-2026-36604 published?

CVE-2026-36604 was published on 2026-06-03 and last updated on 2026-06-17.

CVE-2026-36604

CVE-2026-36604 is a medium-severity vulnerability with a CVSS 3.x base score of 6.5. 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-350.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-34143
Weakness: CWE-350
Published: 2026-06-03
Last modified: 2026-06-17

Description

Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 does not validate the HTTP Host header, enabling DNS rebinding attacks. An external attacker can rebind a domain to the router's internal IP address, extending the CORS wildcard vulnerability (Access-Control-Allow-Origin: *) to internet-originated attacks.

Frequently asked questions

What is CVE-2026-36604?: Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 does not validate the HTTP Host header, enabling DNS rebinding attacks. An external attacker can rebind a domain to the router's internal IP address, extending the CORS wildcard vulnerability (Access-Control-Allow-Origin: *) to internet-originated attacks.
How severe is CVE-2026-36604?: CVE-2026-36604 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-36604 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-36604?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-36604 have an EU (EUVD) identifier?: Yes. CVE-2026-36604 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34143.
When was CVE-2026-36604 published?: CVE-2026-36604 was published on 2026-06-03 and last updated on 2026-06-17.

References

https://github.com/Tymbark7372/MERCUSYS-AC12G/blob/master/advisories/CVE-2026-36604.md

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