Medium severity · published Aug 24, 2022
CVE-2021-4209
A NULL pointer dereference flaw was found in GnuTLS
6.5
CVSS
1.9%
EPSS
No
On KEV
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
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GN
GnuTLS ·
Fixed in gnutls v3.7.3 · source: vendor, NVD
AI
Active IQ Unified Manager · Netapp
All versions, or not specified · source: NVD
EL
Enterprise Linux · Redhat
8.0 · source: NVD
HB
Hci Bootstrap OS · Netapp
All versions, or not specified · source: NVD
SH
Solidfire & Hci Management Node · Netapp
All versions, or not specified · source: NVD
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-4209
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-4209
Third Party Advisory
https://access.redhat.com/security/cve/CVE-2021-4209
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2044156
Patch
https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568
Third Party Advisory
https://gitlab.com/gnutls/gnutls/-/issues/1306
Third Party Advisory
https://gitlab.com/gnutls/gnutls/-/merge_requests/1503
Third Party Advisory
https://security.netapp.com/advisory/ntap-20220915-0005/
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