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.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-9gcg-w975-3rjh Istio: AuthorizationPolicy serviceAccounts regex injection via unescaped dots
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 17 Apr 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-625
References
Metrics threat_severity

None

threat_severity

Moderate


Thu, 16 Apr 2026 12:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 16 Apr 2026 00:45:00 +0000

Type Values Removed Values Added
First Time appeared Istio
Istio istio
Vendors & Products Istio
Istio istio

Wed, 15 Apr 2026 23:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Istio AuthorizationPolicy Incorrect Regex Matching of Dots in serviceAccounts Fields Allows Policy Bypass
Weaknesses CWE-185
CWE-863
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-16T12:04:54.038Z

Reserved: 2026-04-06T20:28:38.394Z

Link: CVE-2026-39350

cve-icon Vulnrichment

Updated: 2026-04-16T11:13:57.554Z

cve-icon NVD

Status : Received

Published: 2026-04-15T23:16:09.477

Modified: 2026-04-15T23:16:09.477

Link: CVE-2026-39350

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-15T22:42:24Z

Links: CVE-2026-39350 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-04-17T06:30:11Z

Weaknesses