Suspicious Telerik UI RadAsyncUpload Request Indicating CVE-2019-18935 Exploitation (via webserver)

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects requests to the Telerik Web UI WebResource handler with the type rau parameter that drives the RadAsyncUpload component targeted by CVE-2019-18935. Threat actors send crafted requests to this endpoint to deserialize a malicious payload and drop a DLL on the server. Traffic to this specific handler and parameter is a strong exploitation signal for vulnerable Telerik deployments.

Reporting behind it

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Suspicious Telerik UI RadAsyncUpload Request Indicating CVE-2019-18935 Exploitation (via webserver)

Pivot detection · T1190 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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