CVE-2026-36604: Mercusys AC12G · Reliance on Reverse DNS Resolution for a Security-Critical Action
Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 16% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 3 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
Until a fix is available, network administrators should consider restricting DNS responses and monitoring for suspicious DNS rebinding activity. Users should follow any future vendor advisories for updates or patches addressing this issue.
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.