CVE-2021-33560 Information

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

Reference

https://dev.gnupg.org/T5466 https://dev.gnupg.org/rCe8b7f10be275bcedb5fc05ed4837a89bfd605c61 https://dev.gnupg.org/T5305 https://dev.gnupg.org/T5328 https://lists.debian.org/debian-lts-announce/2021/06/msg00021.html https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/R7OAPCUGPF3VLA7QAJUQSL255D4ITVTL/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BKKTOIGFW2SGN3DO2UHHVZ7MJSYN4AAB/ https://www.oracle.com/security-alerts/cpuoct2021.html https://www.oracle.com/security-alerts/cpujan2022.html https://www.oracle.com/security-alerts/cpuapr2022.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

NONE

Base Score

NONE

Base Severity

7.5