CVE-2026-31837

HIGH

Istio <1.29.1/1.28.5/1.27.8 - Auth Bypass

Title source: llm
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0028
EPSS Percentile 19.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-200
Status published
Products (3)
istio/istio < 1.27.8 (2 CPE variants)
istio/istio >= 1.28.0-alpha.0, < 1.28.5
istio/istio >= 1.29.0-alpha.0, < 1.29.1
Published Mar 10, 2026
Tracked Since Mar 11, 2026