CVE-2021-39156 HIGH

CVE-2021-39156: Fragments in Path May Lead to Authorization Policy Bypass

Vendor Istio
Product istio
Weakness CWE-863 · Incorrect authorization
Published August 24, 2021
Last update August 4, 2024
View on NVD All CVEs

CVSS base score

8.1/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

August 24, 2021 CVE published
August 4, 2024 Record updated