CVE-2023-35941 - CVE House
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Status published High CVE-2023-35941

Envoy vulnerable to OAuth2 credentials exploit with permanent validity

Vulnerability Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, a malicious client is able to construct credentials with permanent validity in some specific scenarios. This is caused by the some rare scenarios in which HMAC payload can be always valid in OAuth2 filter's check. Versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12 have a fix for this issue. As a workaround, avoid wildcards/prefix domain wildcards in the host's domain configuration.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

envoy
Vulnerable Versions:
>= 1.26.0, < 1.26.4, >= 1.25.0, < 1.25.9, >= 1.24.0, < 1.24.10, < 1.23.12

Timeline

Official Publish: July 25th, 2023
Last Modified: October 24th, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

Weaknesses (CWE)

CWE-116

MITRE ATT&CK TTPs

T1189 Drive-by Compromise
Initial Access
T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1565.002 Stored Data Manipulation
Impact