Jenkins/Kubernetes cannot clone from gitea repository with valid cert - ssl

Question

I am using Jenkins with Kubernetes agents, trying to build a Gitea-hosted git repository using an organizational folder configuration. When my build triggers, I get
stderr: fatal: unable to access 'https://<servername.com>/homelab/java-spring-microservice.git/': server certificate verification failed. CAfile: none
The repository (also hosted within the kubernetes cluster) has a valid LetsEncrypt certificate on its ingress (managed by cert-manager.) I'm able to clone this repo fine from git command-line (without having TLS disabled.)
My Jenkinsfile looks like this:
podTemplate(containers: [
containerTemplate(
name: 'maven',
image: 'maven:3.8.4-openjdk-11',
command: 'sleep',
args: '30d'
)
]) {
node(POD_LABEL) {
stage('Checkout') {
checkout scm
container('maven') {
stage('Build') {
sh '''
mvn clean package
'''
}
}
}
}
}
I've looked around and seen ways to get around this by disabling TLS for the git operation, but that seems wrong-headed to me, since TLS appears to be working. I'll admit to being a bit uncertain of how exactly all this works when things are under kubernetes (where should I be looking to see if the CA trust chain is correct, etc.)

Answer 1

After some digging, I determined that both the version of jenkins/inbound-agent and the version of jenkins itself were built against base images that did not have up-to-date CA trust chains. I was able to resolve the problem by updating to the latest Jenkins, updating the pod template for kubernetes, and updating the kubernetes plugin for jenkins.