By Securonix Threat Labs
Microsoft has released an advisory to address CVE-2022-26809, CVSS score: 9.8, an RCE vulnerability in Remote Procedure Call (RPC) Runtime Library. A remote, unauthenticated attacker could exploit this vulnerability to take control of an affected system.
To prevent exploitation, Securonix recommends blocking port 445 and 135 on the enterprise firewall and per Microsoft’s recommendation, secure all SMB traffic.
We advise customers to use Securonix policy “Suspicious Process Spawned By Remote Procedure Call Service” and/or the below queries to detect exploitation of this vulnerability.
Title: Suspicious Process Spawned By Remote Procedure Call Service
Description: Detects anomalous process spawned by the remote procedure call service (RPC).
Supported Version: 6.3 and 6.4
index = activity AND rg_functionality = “Endpoint Management Systems” AND (deviceaction = “Process Create” OR deviceaction = “Process Create (rule: ProcessCreate)” OR deviceaction = “ProcessRollup2”) AND sourceprocessname = “svchost.exe” AND resourcecustomfield2 CONTAINS “RPCSS” | STATS destinationprocessname
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