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CVE-2021-20230 Detail

Description

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink 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 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-295 Improper Certificate Validation Red Hat, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-20230
NVD Published Date:
02/23/2021
NVD Last Modified:
06/01/2022
Source:
Red Hat, Inc.