CVE-2021-39156

HIGH
Published Aug 24, 20214y ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
High
Find Similar
Published Aug 24, 2021 4y ago
Last Modified Jun 17, 2026 2w ago

Description

Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability None

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 2

CWE-706
CWE-863 Incorrect Authorization Authorization

Affected Products 3

VendorProductVersionRange
istioistio* <1.9.8
istioistio*≥1.10.0  –  <1.10.3
istioistio*≥1.11.0  –  <1.11.1

References 2

  • github.com https://github.com/istio/istio/security/advisories/GHSA-hqxw-mm44-gc4r
    Third Party Advisory
  • istio.io https://istio.io/latest/news/security/istio-security-2021-008
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.