What is the CVSS score of EUVD-2026-23128?

EUVD-2026-23128 has a CVSS 3.1 base score of 5.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N. EPSS exploitation probability: 0.0%.

Is there a patch available for EUVD-2026-23128?

Yes, a patch is available for EUVD-2026-23128. Update the affected software to the latest version immediately.

Istio EUVD-2026-23128

| CVE-2026-39350 MEDIUM

Incorrect Regular Expression (CWE-185)

2026-04-15 GitHub_M

GHSA-9gcg-w975-3rjh

Information Disclosure Istio

5.4

CVSS 3.1 · GitHub Advisory

View

Vulnerability Assessment

Weakness

CWE

CWE-185

OWASP Top 10:2025

A05:2025 - Injection

ASVS 5.0

V2 - Validation and Business Logic Incorrect input validation

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).

Patch available 0.0% exploitation probability (EPSS)

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AnalysisAIv1 – Jul 26, 2026

Authorization policy bypass in Istio service mesh due to incorrect handling of dots (.) as regular expression metacharacters in service account names. In affected versions 1.25.0–1.27.8, 1.28.0–1.28.5, and 1.29.0–1.29.1, the serviceAccounts and notServiceAccounts fields in AuthorizationPolicy misinterpret dots, causing an ALLOW rule for e.g. cert-manager.io to also match cert-manager-io and similar variants, while a DENY rule fails to block them. An authenticated attacker with low privileges can exploit this to gain unauthorized access or bypass restrictions. No active exploitation or public proof-of-concept has been identified; EPSS indicates very low exploitation probability (0.03%). Patches are available.

Affected VersionsENISA

istio 1.25.0, < < 1.27.9

istio 1.28.0, < 1.28.6

istio 1.29.0, < 1.29.2

Affected Packages

go istio.io/istio fix: 0.0.0-20260403004500-692e460c342d

euvd istio_1_25_0 fix: 1.27.9

euvd istio_1_28_0 fix: 1.28.6

euvd istio_1_29_0 fix: 1.29.2

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 4 packages in go, euvd

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

GitHub Advisory PRIMARY 5.4 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

SUSE MEDIUM

Red Hat 5.4 MEDIUM

Primary rating from GitHub Advisory.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Patch released

Apr 23, 2026 - 20:00 nvd

Patch available

Apr 16, 2026 - 22:01 EUVD

CVE Published

Apr 15, 2026 - 22:42 nvd

MEDIUM 5.4

DescriptionGitHub Advisory

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.

Threat Intelligence Overview

EPSS Score

0.0%

Top 93% exploitable

Threat Intel

1 source

Data Quality

7 sources

Confidence: High

EUVD

NVD

CVE.org

EPSS

Vulnrichment GHSA Vendor

GitHub

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity MEDIUM

CISA KEV No

Public POC No

EPSS 0.0%

Patch available Yes

Active threat No

Deciding rule

MEDIUM severity (CVSS 4.0-6.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation

None

System Exposure· derived

Open

Automatable

Human Impact· derived

Medium

Technical Impact

Partial

Priority Score

Low Medium High Critical

KEV: 0

EPSS: 0

CVSS: +27

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.