NetSight
medium5.4

CVE-2026-39350

Istio: AuthorizationPolicy serviceAccounts regex injection via unescaped dots

Impact

Istio is an open platform to connect, manage, and secure microservices. In versions 1.25.0 through 1.27.8, 1.28.0 through 1.28.5, 1.29.0, and 1.29.1, the serviceAccounts and notServiceAccounts fields in AuthorizationPolicy incorrectly interpret dots (.) as a regular expression matcher. Because . is a valid character in a service account name, an AuthorizationPolicy ALLOW rule targeting a service account such as cert-manager.io also matches cert-manager-io, cert-managerXio, etc. A DENY rule targeting the same name fails to block those variants. Fixes are available in versions 1.29.2, 1.28.6, and 1.27.9.

Affected packages

EcosystemPackageAffectedFixed in
goistio.io/istio>= 0.0.0-20241024090207-0bf27d49ba4b, < 0.0.0-20260403004500-692e460c342d0.0.0-20260403004500-692e460c342d

Affected products

VendorProductAffected versions
IstioIstio
from 1.25.0 before 1.27.9
from 1.28.0 before 1.28.6
from 1.29.0 before 1.29.2

Weakness classification

References