There have been two recent Security Updates for both Jenkins Core and for multiple Plugins.
Jenkins Core Updates
Jenkins versions 2.107 and 2.89.4 have just been released that fix multiple security vulnerabilities.
For an overview of what was fixed, see the security advisory. For an overview on the possible impact of these changes on upgrading Jenkins LTS, see the LTS upgrade guide.
Jenkins Plugin Updates
Multiple Jenkins plugins have recently updates that fix several security vulnerabilities.
For an overview of these security fixes, see the security advisory.