CVE-2026-74232 Zbtlink MQWrt yunmgrd Cloud C2 Implant
A hardcoded backdoor in Zbtlink and MoreQuick router firmware allows remote attackers to execute arbitrary commands as root and steal credentials via an unauthenticated UDP channel.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-74232?
CVE-2026-74232 is a critical vulnerability in MoreQuick AP522, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Zbtlink L3_V2_8 firmware 3.0.0.4.528, Zbtlink WE826-T2 firmware 19.1101, Zbtlink ZBT-7628 firmware 1.0.0.2.007, Zbtlink ZBT-ZBT7621 firmware 1.0.0.3.001, MoreQuick MQAC-7620, MQAC-7620A, MQAP-7620, MQAP-7620A, and MQAP-7628 firmware 1.0.0.2.000, AP522 firmware 1.0.0.2.014, AP7628 and HC5661A firmware 3.0.0.4.380, APG721B firmware 19.0809, HK300 firmware 1.0.0.2.032, and MAP-N10 firmware 1.0.0.2.044 ship a backdoor command-and-control implant (yunmgrd) reachable over an unauthenticated cleartext UDP channel to a hardcoded C2 server. A remote unauthenticated attacker on the network path can hijack the channel and execute arbitrary commands as root. The attacker can also modify DNS entries, exfiltrate PPPoE credentials, and open reverse SSH tunnels.
Which versions are affected by CVE-2026-74232?
How do I fix CVE-2026-74232?
No fix has been published for CVE-2026-74232 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-74232 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74232 exists.
Sources
Also known as GHSA-jgcj-chrm-4hhc.