CVE-2021-4209
Description
A NULL pointer dereference flaw was found in GnuTLS. As Nettle's hash update functions internally call memcpy, providing zero-length input may cause undefined behavior. This flaw leads to a denial of service after authentication in rare circumstances.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Novell Inc.
commercial·US
netapp
commercial·US
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
АО «НТЦ ИТ РОСА»
commercial·RU
gnu
oss-project·USaka g. nu
Red Hat Inc.
commercial·USaka redhat, red hat
and 9 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
2 techniques Impact
Initial Access
References
https://access.redhat.com/security/cve/CVE-2021-4209
access.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2044156
bugzilla.redhat.com
https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568
gitlab.com
and 23 more references View all →
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