CVE Vulnerability

CVE-2021-20230

A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality.

5 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 10 / Impact : 2.9

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

Scope

7.5 /10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References
Link Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1925226 Issue Tracking Third Party Advisory
https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9 Patch Third Party Advisory
https://security.gentoo.org/glsa/202105-02 Third Party Advisory
Configurations

Configuration 1

cpe:2.3:a:stunnel:stunnel:*:*:*:*:*:*:*:*
Information

Published : 2021-02-23 05:15

Updated : 2022-06-01 06:05

NVD link : CVE-2021-20230

Mitre link : CVE-2021-20230

Products Affected
No products.
CWE
CWE-295

Improper Certificate Validation