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» GHSA-66mf-3gg5-cm75
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.
Basic information
Type
unreviewed
Severity
high Advisory on GitHub
Open advisory ↗ Repository advisory
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Source code
Not specified Published (advisory)
2026-06-03 18:33:11 UTC
Updated
2026-06-03 21:30:29 UTC
NVD published
2026-06-03
EPSS Score
Score
Percentile
0.02%
3.87%
CVSS Scores
Base score
Version
Severity
Vector
8.8
3.1
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CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
CWEs
CWE id
Name
CWE-307
Improper Restriction of Excessive Authentication Attempts
cvelogic
Threat Intelligence