CVE-2021-33560 is a high-severity vulnerability affecting Libgcrypt versions before 1.8.8 and 1.9.x before 1.9.3, specifically impacting ElGamal encryption used in products like OpenPGP, Debian, Fedora, and Oracle. The flaw stems from insufficient exponent blinding and an improperly chosen window size, making it susceptible to side-channel attacks against mpi_powm. This network-exploitable vulnerability has low attack complexity and could lead to high confidentiality impact, allowing attackers to potentially decrypt sensitive information. Currently, there is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 1.8.8CPE matchmatch criteria | cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:* | ||
>= 1.9.0, < 1.9.3CPE matchmatch criteria | cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:* | ||
9.0CPE matchmatch criteria | cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | ||
33CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | ||
34CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
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.
Jun 8, 2021libgcrypt: mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm
Jun 2, 2021