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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:NIntegrityNone
A:NAvailabilityNone
Weaknesses
Affected Products
Novell Inc.
commercial·US
Red Hat Inc.
commercial·USaka red hat
ООО «Ред Софт»
commercial·RUaka red soft
АО «ИВК»
commercial·RUaka ivk
Сообщество свободного программного обеспечения
oss-projectaka fsf
stunnel
oss-project
and 5 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Collection
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 →
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