CVE Catalog

CVE-2026-31837

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.38%

30th percentile - higher than 30% of all known CVEs

Summary

A vulnerability in Istio causes hardcoded defaults to be used when the JWKS resolver is unavailable or fetch fails, bypassing RequestAuthentication configuration. Affects versions prior to 1.29.1, 1.28.5, and 1.27.8.

Risk Assessment

The organization risks that request authentication may be bypassed, potentially allowing unauthorized access to microservices.

Recommendation

Immediately upgrade Istio to version 1.29.1, 1.28.5, or 1.27.8 depending on the release line used.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS