High severity · published Jun 8, 2021
CVE-2021-33560
Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm, and the window…
7.5
CVSS
2.4%
EPSS
No
On KEV
Description
Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm, and the window size is not chosen appropriately. This, for example, affects use of ElGamal in OpenPGP.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Communications Cloud Native Core Binding Support Function · Oracle
1.11.0 · source: NVD
CC
Communications Cloud Native Core Network Function Cloud Native Environment · Oracle
1.9.0; 1.10.0 · source: NVD
CC
Communications Cloud Native Core Network Repository Function · Oracle
1.14.0; 1.15.0; 1.15.1 · source: NVD
CC
Communications Cloud Native Core Network Slice Selection Function · Oracle
1.8.0 · source: NVD
CC
Communications Cloud Native Core Service Communication Proxy · Oracle
1.15.0 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
LI
Libgcrypt · Gnupg
before 1.8.8; 1.9.0 before 1.9.3 · 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-2021-33560
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33560
Release Notes
https://dev.gnupg.org/T5305
Vendor Advisory
https://dev.gnupg.org/T5328
Release Notes
https://dev.gnupg.org/T5466
Patch
https://dev.gnupg.org/rCe8b7f10be275bcedb5fc05ed4837a89bfd605c61
Mailing List
https://lists.debian.org/debian-lts-announce/2021/06/msg00021.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BKKTOIGFW2SGN3DO2UHHVZ7MJSYN4AAB/
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