Suspicious UPSTYLE Command Channel Pattern in Web Requests via CVE-2024-3400

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.004DNS
Exfiltration
Impact

What it detects

This rule detects web requests carrying the base64 command pattern wrapped in img brackets used by the UPSTYLE backdoor deployed in Operation MidnightEclipse against CVE-2024-3400. The backdoor reads operator commands embedded in crafted requests that surface in the device error log. Detecting this pattern surfaces the covert command channel used to control the compromised firewall.

Reporting behind it

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Suspicious UPSTYLE Command Channel Pattern in Web Requests via CVE-2024-3400

Pivot detection · T1071.004 · 9 related

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