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CVE-2021-20230

Published: Feb 23, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-295
NVD MITRE
7.5CVSSHIGH
EPSS Score
1.2%
Top 36.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-295

Affected Products

Red Hat Enterprise LinuxRed Hat Inc.
On-premOS
Operating Systems / linux-distro
SUSE Linux Enterprise Server for SAP ApplicationsNovell Inc.
On-premOS
Operating Systems / linux-distro
SUSE Enterprise StorageNovell Inc.
On-prem
Databases / data-warehouse-analytics
SUSE Linux Enterprise High Performance ComputingNovell Inc.
On-premOS
Operating Systems / linux-distro
Suse Linux Enterprise ServerNovell Inc.
On-premOS
Operating Systems / linux-distro
red hat inc.commercialUSOperating Systemsaka red hat
novell inc.commercialUSOperating Systems
and 13 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9
github.com
https://redos.red-soft.ru/support/secure/uyazvimosti/uyazvimost-stunnel-cve-2021-20230/
redos.red-soft.ru
https://access.redhat.com/security/cve/CVE-2021-20230
access.redhat.com
and 5 more references View all →

Timeline

Published
Feb 23, 2021
Last Updated
Nov 21, 2024

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