cbcvebase.
CVE-2018-1002105
published 2018-12-05

CVE-2018-1002105: In all Kubernetes versions prior to v1.10.11, v1.11.5, and v1.12.3, incorrect handling of error responses to proxied upgrade requests in the kube-apiserver…

PriorityP184critical9.8CVSS 3.0
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
86.98%
99.7th percentile
In all Kubernetes versions prior to v1.10.11, v1.11.5, and v1.12.3, incorrect handling of error responses to proxied upgrade requests in the kube-apiserver allowed specially crafted requests to establish a connection through the Kubernetes API server to backend servers, then send arbitrary requests over the same connection directly to the backend, authenticated with the Kubernetes API server's TLS credentials used to establish the backend connection.

Affected

34 ranges· showing 25
VendorProductVersion rangeFixed in
debiankubernetes< kubernetes 1.17.4-1 (bookworm)kubernetes 1.17.4-1 (bookworm)
github.comkubernetes_kubernetes>= 0 < 1.10.111.10.11
github.comkubernetes_kubernetes>= 1.11.0 < 1.11.51.11.5
github.comkubernetes_kubernetes>= 1.12.0 < 1.12.31.12.3
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes
kuberneteskubernetes>= 0 < 1.17.4-11.17.4-1
kuberneteskubernetes>= 0 < 1.17.4-11.17.4-1
kuberneteskubernetes>= 0 < 1.17.4-11.17.4-1
kuberneteskubernetes>= 0 < 1.17.4-11.17.4-1
kuberneteskubernetes1.0.0 – 1.9.11
kuberneteskubernetes1.10.0 – 1.10.10
kuberneteskubernetes1.11.0 – 1.11.4
kuberneteskubernetes1.12.0 – 1.12.2
kuberneteskubernetes>= unspecified < v1.10.11v1.10.11
kuberneteskubernetes>= unspecified < v1.11.5v1.11.5

Detection & IOCsextracted from sources · hover to see the quote

url/apis/metrics.k8s.io/
otherX-Remote-User
otherX-Remote-Group
othersystem:serviceaccount:kube-system:horizontal-pod-autoscaler
  • Detect HTTP Upgrade requests to the kube-apiserver that receive a non-101 response code but maintain an open proxy connection — this is the core exploit primitive (missing 101 Switching Protocols check in upgradeaware.go).
  • Alert on use of X-Remote-User / X-Remote-Group impersonation headers arriving at the kube-apiserver, especially from pods that do not normally communicate with the API server.
  • Monitor access to /root/.docker/config.json and /home/*/.docker/config.json from container processes — used by attackers to harvest Docker Hub credentials post-exploitation.
  • ·The vulnerability also enables privilege escalation via pod exec/attach/portforward requests routed through the kubelet API, not only through aggregated API servers.
  • ·Service Catalog aggregated API server is installed by default on OpenShift from version 3.7 and on cloud-provider-deployed Kubernetes clusters, expanding the attack surface.
  • ·Exploit traffic over the hijacked proxy connection is authenticated with the kube-apiserver's own TLS credentials, making it appear as legitimate server-to-server traffic in backend logs.

CVSS provenance

nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
CVEs like this are exactly what “Exploited This Week” covers.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.