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Fencer Intel
high 7.7

CVE-2026-42965 json

Openshift/router: openshift/router: cloud metadata ssrf via fqdn-typed endpointslice bypasses destination validation

published 5mo ago modified 5d ago also EUVD-2026-33275

cvss
7.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits
0
none known

Summary

A flaw was found in the OpenShift Router. A user with EndpointSlice write access can exploit this vulnerability by creating a Service backed by an FQDN (Fully Qualified Domain Name) EndpointSlice that resolves to a cloud metadata endpoint. This allows the router to proxy requests to the cloud metadata endpoint, leading to the disclosure of instance credentials and other sensitive metadata. This bypasses previous security measures for validating IP addresses.

Patch / fix

  • Red Hat Red Hat OpenShift Container Platform 4.17 1789938693
  • Red Hat Red Hat OpenShift Container Platform 4.18 1788578875
  • Red Hat Red Hat OpenShift Container Platform 4.19 1786771399
  • Red Hat Red Hat OpenShift Container Platform 4.20 1786496552
  • Red Hat Red Hat OpenShift Container Platform 4.21 1786498169
  • Red Hat Red Hat OpenShift Container Platform 4.22 1786584196

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-42965 updated cvss 7.7

openshift/router: openshift/router: cloud metadata SSRF via FQDN-typed EndpointSlice bypasses destination validation

  • Red Hat OpenShift Container Platform 4 openshift4/ose-haproxy-router Red Hat OpenShift Container Platform 5 openshift5/ose-haproxy-router-rhel9
    affected: no fix available
  • Red Hat OpenShift Container Platform 4.17 openshift4/ose-haproxy-router-rhel9 1789938693
    fixed: vendor fix RHSA-2026:70587
  • Red Hat OpenShift Container Platform 4.18 openshift4/ose-haproxy-router-rhel9 1788578875
    fixed: vendor fix RHSA-2026:65852
  • Red Hat OpenShift Container Platform 4.19 openshift4/ose-haproxy-router-rhel9 1786771399
    fixed: vendor fix RHSA-2026:57408
  • Red Hat OpenShift Container Platform 4.20 openshift4/ose-haproxy-router-rhel9 1786496552
    fixed: vendor fix RHSA-2026:54583
  • Red Hat OpenShift Container Platform 4.21 openshift4/ose-haproxy-router-rhel9 1786498169
    fixed: vendor fix RHSA-2026:54602
  • Red Hat OpenShift Container Platform 4.22 openshift4/ose-haproxy-router-rhel9 1786584196
    fixed: vendor fix RHSA-2026:54770
  • Red Hat OpenShift Container Platform 4.17 openshift4/frr-rhel9 1789938330, openshift4/ose-cli-rhel9 1789937904, openshift4/ose-pod-rhel9 1789937463, openshift4/ose-etcd-rhel9 1789937632, openshift4/ose-tests-rhel9 1790075131, openshift4/ose-tools-rhel9 1790073665, +180 more Red Hat OpenShift Container Platform 4.18 openshift4/frr-rhel9 1788576352, openshift4/ose-cli-rhel9 1788576309, openshift4/ose-pod-rhel9 1788575535, openshift4/ose-etcd-rhel9 1788576053, openshift4/ose-tests-rhel9 1788579480, openshift4/ose-tools-rhel9 1788576163, +180 more Red Hat OpenShift Container Platform 4.19 openshift4/frr-rhel9 1786760573, openshift4/ose-cli-rhel9 1787046152, openshift4/ose-pod-rhel9 1786802866, openshift4/ose-etcd-rhel9 1786767009, openshift4/ose-tests-rhel9 1787106695, openshift4/ose-tools-rhel9 1787105251, +182 more Red Hat OpenShift Container Platform 4.20 openshift4/frr-rhel9 1786493981, openshift4/ose-cli-rhel9 1786494900, openshift4/ose-pod-rhel9 1786498817, openshift4/ose-etcd-rhel9 1786494149, openshift4/ose-tests-rhel9 1786545242, openshift4/ose-tools-rhel9 1786543651, +183 more Red Hat OpenShift Container Platform 4.21 openshift4/frr-rhel9 1786497121, openshift4/ose-cli-rhel9 1786496647, openshift4/ose-pod-rhel9 1786502473, openshift4/ose-etcd-rhel9 1786497722, openshift4/ose-tests-rhel9 1786526472, openshift4/ose-tools-rhel9 1786524417, +180 more Red Hat OpenShift Container Platform 4.22 openshift4/frr-rhel9 1786583427, openshift4/ose-cli-rhel9 1786583327, openshift4/ose-pod-rhel9 1786606091, openshift4/ose-etcd-rhel9 1786549839, openshift4/ose-tests-rhel9 1786607829, openshift4/ose-tools-rhel9 1786602789, +182 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
CISA ADP 3.1 7.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Affected products

  • Red Hat Red Hat OpenShift Container Platform 4.17
  • Red Hat Red Hat OpenShift Container Platform 4.18
  • Red Hat Red Hat OpenShift Container Platform 4.19
  • Red Hat Red Hat OpenShift Container Platform 4.20
  • Red Hat Red Hat OpenShift Container Platform 4.21
  • Red Hat Red Hat OpenShift Container Platform 4.22
  • Red Hat Red Hat OpenShift Container Platform 4
  • Red Hat Red Hat OpenShift Container Platform 5

Classification

Weakness
  • CWE-918 Server-Side Request Forgery

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.