CVE-2021-4209
6.5CVSSMEDIUM
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.
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
and 21 more affected products View all →
Attack Graph
Products CVE Techniques Tactics
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Exploitability
Official Patch Available
MITRE ATT&CK
2 techniques Impact
Initial Access
References
https://gitlab.com/gnutls/gnutls/-/issues/1306
gitlab.com
https://bugzilla.redhat.com/show_bug.cgi?id=2044156
bugzilla.redhat.com
https://access.redhat.com/security/cve/CVE-2021-4209
access.redhat.com
and 23 more references View all →
Timeline
Published
Aug 24, 2022
Last Updated
Nov 21, 2024
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