CVE-2026-82976
Image-customization-controller: unauthenticated plaintext image server with directory listing exposes ignition images containing cluster pull secret
What happened?
A flaw was found in the image-customization-controller used in OpenShift's bare metal provisioning stack. The controller registers an HTTP file server on port 8084 with no authentication. The custom imageFileSystem implementation exposes a browsable HTML directory listing of all registered images at the root path. The only access control on per-host images is the random UUID filename; the directory listing discloses those UUIDs to any caller on the provisioning network. Each served image embeds an Ignition config containing the base64-encoded cluster pull secret, optional IRONIC_RAMDISK_SSH_KEY, proxy settings, and per-host NetworkManager keyfiles. An adjacent network attacker can enumerate all image UUIDs via directory listing, download any image, extract the embedded Ignition config, and recover the cluster pull secret and SSH key.
Evidence pkg/imagehandler/imagefilesystem.go — root directory is browsable and enumerates all UUID image names ```go func (f *imageFileSystem) Readdir(n int) ([]fs.FileInfo, error) { f.mu.Lock() defer f.mu.Unlock() result := []fs.FileInfo{} for _, im := range f.images { result = append(result, im) } return result, nil }
func (f *imageFileSystem) Open(name string) (http.File, error) { f.log.Info("Open", "path", name) if name == "/" { return f, nil } ... ```
cmd/controller/main.go — file server bound on all interfaces without auth or TLS ```go http.Handle("/", http.FileServer(imageServer.FileSystem()))
go func() { server := &http.Server{ Addr: imagesBindAddr, // default ":8084" ReadHeaderTimeout: 5 * time.Second, } err := server.ListenAndServe() ```
pkg/ignition/service_config.go:94-100 — pull secret is embedded in every served image ```go func (b *ignitionBuilder) authFile() ignition_config_types_32.File { source := "data:;base64," + strings.TrimSpace(b.ironicAgentPullSecret) return ignition_config_types_32.File{ Node: ignition_config_types_32.Node{Path: "/etc/authfile.json"}, ... ```
Attack Pattern Adjacent provisioning-network client → GET / lists UUID image names → download ISO/initramfs → extract embedded Ignition → recover cluster pull secret and SSH key.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| openshift4/ose-image-customization-controller-rhel8Red Hat | Default status: affected | See vendor advisory |
| openshift4/ose-image-customization-controller-rhel9Red Hat | Default status: affected | See vendor advisory |
| openshift5/ose-image-customization-controller-rhel9Red Hat | Default status: affected | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.