Abnormal User-Agent value in GET request

I came a cross some WAF logs that alert on Illegal URL Length. When I investigated the logs, I noticed weird user-agent value: 7375716F62756415670E1005007A7C68721200333F23323F770233342F2E37

I have been trying to search for this value and for that format/pattern in google without any success. It seems like some kind of hashed value.

Has anyone come across such a thing? Do you think this is some kind of covert channel attempt? or just user-agent spoofing that went wrong?