CVE-2026-36606
High
Description
Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 encrypts configuration backups with a hardcoded DES key using single DES in ECB mode. An attacker who obtains a backup file can decrypt it to recover all stored credentials including admin password, WiFi PSK, and DDNS credentials.
SeverityHigh
CVSS7.1
Exploit probability—
ProductAC12G (EU) V1 router
PublishedJun 3, 2026
First seenJun 3, 2026
Weakness typeCWE-798Hard-coded credentials
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Mercusys AC12G (EU) V1 router | AC12G(EU)_V1_200909 | — |
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