This indicates an attack attempt to exploit an HTTP Request Smuggling vulnerability in SAP Netweaver.
The vulnerability is due to improper handling of HTTP requests. A remote attacker may be able to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.
SAP NetWeaver and ABAP Platform, Versions - KERNEL 7.22, 8.04, 7.49, 7.53, 7.77, 7.81, 7.85
SAP Web Dispatcher, Versions - 7.49, 7.53, 7.77, 7.81, 7.85, 7.22EXT, 7.86, 7.87
SAP Content Server, Version - 7.53
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.
https://wiki.scn.sap.com/wiki/display/PSR/SAP Security Patch Day - February 2022