CVE-2026-31838CWE-863

Istio HTTP debug endpoints on port 15014 to enforce namespace-based authorization, preventing cross-namespace proxy data access.

Medium · published March 10, 2026

CVSS v4.0
6.9
EPSS
0%
Percentile
29.9
In the wild
Unconfirmed
What it is

Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a vulnerability in Envoy RBAC header matching could allow authorization policy bypass when policies rely on HTTP headers that may contain multiple values. An attacker could craft requests with multiple header values in a way that causes Envoy to evaluate the header differently than intended, potentially bypassing authorization checks. This may allow unauthorized requests to reach protected services when policies depend on such header-based matching conditions. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8.

The record
Technical detail
CVSS v4.0
6.9 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N
EPSS
0.00372 · 29.9th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-03-10T21:58Z
EPSS history
Timeline
  • 10 MAR 21:58Z
    Istio HTTP debug endpoints on port 15014 to enforce namespace-based authorization, preventing cross-namespace proxy data access.
    cvelistv5