CVE-2026-39350
Istio AuthorizationPolicy Incorrect Regex Matching of Dots in serviceAccounts Fields Allows Policy Bypass
CVSS Score
5.4
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-185 CWE-863 |
| Vendor | istio |
| Product | istio |
| Published | Apr 15, 2026 |
| Last Updated | Apr 16, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
istio / istio
>= 1.25.0, < < 1.27.9 >= 1.28.0, < 1.28.6 >= 1.29.0, < 1.29.2