Zyxel EMG2926 Routers Command Injection Vulnerability

[ Why it matters ]Priority signals

• Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2023-09-18
• Known to be used in ransomware campaigns
• EPSS: 33% chance of exploitation in the next 30 days (higher than 98% of CVEs)

[ Description ]Official description

A command injection vulnerability was discovered on the Zyxel EMG2926 home router with firmware V1.00(AAQT.4)b8. The vulnerability is located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute arbitrary commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.

CISA: Zyxel EMG2926 routers contain a command injection vulnerability located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute malicious commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 9 Oct 2023): Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• www.exploit-db.com/exploits/41782ExploitThird Party AdvisoryVDB Entry
• www.cisa.gov/known-exploited-vulnerabilities-catalogUS Government Resource