We have an error in Jenkins today all of a sudden , No changes done in recent days..

When starting jenkins, within milli seconds we are running with below error.

 INFO    org.eclipse.jetty.server.Server#doStart: jetty-9.4.43.v20210629; built: 2021-06-30T11:07:22.254Z; git: 526006ecfa3af7f1a27ef3a288e2bef7ea9dd7e8; jvm 1.8.0_352-b08
2023-01-20 10:13:58.102+0000 [id=1]     INFO    o.e.j.w.StandardDescriptorProcessor#visitServlet: NO JSP Support for /jenkins, did not find org.eclipse.jetty.jsp.JettyJspServlet
2023-01-20 10:13:58.926+0000 [id=1]     INFO    o.e.j.s.s.DefaultSessionIdManager#doStart: DefaultSessionIdManager workerName=node0
2023-01-20 10:13:58.926+0000 [id=1]     INFO    o.e.j.s.s.DefaultSessionIdManager#doStart: No SessionScavenger set, using defaults
2023-01-20 10:13:58.927+0000 [id=1]     INFO    o.e.j.server.session.HouseKeeper#startScavenging: node0 Scavenging every 600000ms
2023-01-20 10:14:00.689+0000 [id=1]     SEVERE  hudson.WebAppMain#contextInitialized: Failed to initialize Jenkins
java.lang.ClassNotFoundException: org.springframework.util.Assert
2023-01-20 10:58:30.109+0000 [id=1]     SEVERE  winstone.Logger#logInternal: Container startup failed
java.lang.ClassNotFoundException: org.springframework.util.Assert