Cases2 cases
1 to 2 of 2
IL-0405An expired AWS Load Balancer Controller webhook certificate left no healthy targets and took BSEE SaaS downPortSwigger2026- Symptoms
From 10:00 UTC on 11 January 2026 every BSEE SaaS instance in PortSwigger's US and Canada regions was unavailable: customers could not open the Web UI or start scans. The platform team learned of it only when customers reported it through support at 09:52 UTC the next day.
- Trigger
The upgrade of the AWS Load Balancer Controller from v1.14.1 to v1.16.0 on 28 November 2025 left an orphaned webhook TLS secret that cert-manager could not renew, and the certificate in it expired on 8 January 2026.
- Root cause
- Component
- Contributing factor
- Detection
Customers reported the outage through support at 09:52 UTC on 12 January 2026, almost 24 hours after impact began, and the platform team began investigating at 10:00 UTC.
- Remediation
- Deleted the orphaned aws-load-balancer-tls secrets in the US and Canada clusters
- Redeployed the AWS Load Balancer Controller configuration with Helm
- Verified that new certificates were generated and the webhooks worked again
- Action items
- Audit all clusters for orphaned secrets that have no owning Certificate resource and resolve them
- Add high-level application access alerting for each SaaS cluster from an external probe
IL-0522An ingress-nginx chart upgrade deleted the jenkins.io Ingress and Fastly served HTTP/503 errors for hoursJenkins project2021- Symptoms
At 11:32 UTC on 18 November 2021, a user reported in the jenkinsci/jenkins Gitter channel that https://www.jenkins.io/doc/pipeline/steps/ was answering HTTP/503 errors with the message "Guru meditation" from Fastly's varnish.
- Trigger
The ingress-nginx Helm chart was upgraded from 4.0.6 to 4.0.8 at 10:42 UTC, and the new chart added an admission webhook rule that forbids Nginx configuration blocks in Ingress annotations.
- Root cause
- Component
- Contributing factor
- Detection
A user reported in the jenkinsci/jenkins Gitter channel at 11:32 UTC that a jenkins.io page answered HTTP/503 errors, and status.jenkins.io reported the incident at 11:49 UTC.
- Remediation
- Disabled the automated systems, rolled the ingress-nginx chart back to 4.0.6 and deleted the admission webhook by hand
- Removed the forbidden annotations from the jenkins.io configuration
- Upgraded the jenkins.io Helm chart to the last version known to work with ingress-nginx 4.0.8
- Redeployed the jenkins.io Helm chart through the automated system and told Fastly to drop all cached pages
- Action items
- Always read the changelog in depth when updating the ingress controllers, with two people pairing in real time
- Add custom Datadog monitoring for www.origin.jenkins.io so that such an outage is detected
- Make the monitor send the Host header www.jenkins.io so it is not redirected to Fastly
- Check a set of pages, such as the pipeline steps page, not only the front page
- Consider an ephemeral k3s end-to-end test before deploying to production
- Lessons
Trusting a patch version of a Helm chart for the Ingress controller without reading its changelog in depth let a new admission rule remove the jenkins.io Ingress in production. Without monitoring on origin.jenkins.io, a user found the outage. A complete staging cluster with the same DNS setup would have caught the problem before production.
These 2 cases involve Admission webhook and Helm. kubegap audits a Kubernetes cluster for gaps like these, read-only, from Claude Code or Codex; its checks cite public reports like the ones in this library.
By root cause1
Breaking change in an upgrade2 cases
- Component
- Contributing factor
- Organisation