Description
Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a user of Istio is impacted if the JWKS resolver becomes unavailable or the fetch fails, exposing hardcoded defaults regardless of use of the RequestAuthentication resource. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8.
Affected products
istio: istio
References8
- github.com/istio/istio/security/advisories/GHSA-v75c-crr9-733c Vendor Advisory
- access.redhat.com/errata/RHSA-2026:10184
- access.redhat.com/errata/RHSA-2026:5948
- access.redhat.com/errata/RHSA-2026:5950
- access.redhat.com/errata/RHSA-2026:5952
- access.redhat.com/security/cve/CVE-2026-31837
- bugzilla.redhat.com/show_bug.cgi?id=2446344
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31837…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 39 · as of 12 November 2026
- CWE
- CWE-200CWE-1392
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.