CVE-2025-7342
📋 TL;DR
This vulnerability allows attackers with access to Kubernetes Image Builder build VMs to modify Windows images during creation, potentially injecting backdoors or malicious code. Only Kubernetes clusters using VM images created via the vulnerable Image Builder project are affected. The attack requires compromising the build environment itself.
💻 Affected Systems
- Kubernetes Image Builder
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of Kubernetes clusters using maliciously modified Windows node images, enabling persistent root access across all affected nodes.
Likely Case
Limited impact due to the requirement of build VM access; most organizations would detect unauthorized build environment access before image deployment.
If Mitigated
Minimal impact if build environments are properly isolated and monitored, and images are validated before deployment.
🎯 Exploit Status
Exploitation requires access to the build VM during image creation, which typically requires compromising the build infrastructure first.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Kubernetes Image Builder repository for latest secure version
Vendor Advisory: https://groups.google.com/g/kubernetes-security-announce/c/tuEsLUQu_PA
Restart Required: No
Instructions:
1. Update Kubernetes Image Builder to latest version. 2. Rebuild all Windows images using Nutanix or VMware OVA providers. 3. Replace existing vulnerable images with newly built secure images.
🔧 Temporary Workarounds
Disable default credentials manually
allManually disable default credentials in Windows image build scripts before building images
Modify build scripts to ensure default credentials are disabled throughout the entire build process
Use alternative image providers
allTemporarily switch to non-vulnerable image providers for Windows builds
Configure Image Builder to use providers other than Nutanix or VMware OVA for Windows images
🧯 If You Can't Patch
- Isolate build environments with strict access controls and monitoring
- Implement image signing and verification before deploying to production clusters
🔍 How to Verify
Check if Vulnerable:
Check if you're using Kubernetes Image Builder for Windows images with Nutanix or VMware OVA providers and review build logs for credential usageCheck Version:
Check Kubernetes Image Builder version in your build configurationVerify Fix Applied:
Verify new images don't contain default credentials by checking image metadata and testing authentication📡 Detection & Monitoring
Log Indicators:
- Unauthorized access to build VMs
- Unexpected modifications during image build process
- Default credential usage in build logs
Network Indicators:
- Unexpected connections from build VMs
- Suspicious traffic during image creation
SIEM Query:
source="build-vm" AND (event="credential-usage" OR event="unauthorized-access")