Protection Mechanism Failure in Istio - CVE-2026-31837
Published: April 20, 2026
Vulnerability identifier: #VU126607
CSH Severity: Medium
CVSS v4.0: 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:U/U:Green
CVE-ID: CVE-2026-31837
CWE-ID: CWE-693
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Istio
Affected software:
Istio
Istio
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper handling of jwks resolver failures in jwks resolver handling when the jwks resolver becomes unavailable or a fetch fails. A remote attacker can trigger jwks resolver failure conditions to disclose sensitive information.
Hardcoded default keys may be exposed regardless of use of the RequestAuthentication resource.
How to mitigate CVE-2026-31837
Install security update from vendor's website.