CVE-2021-33560
Published: 8 June 2021
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.
Notes
Author | Note |
---|---|
mdeslaur | This CVE was originally for the issue that is now CVE=2021-40528 but somehow got switched to the exponent blinding issue instead. The fix to add exponent blinding appears to only have been added to 1.9.x but never backported to 1.8.x, contrary to the CVE description The commit below was never backported to 1.8.x because the upstream developers consider this hardening and not a security issue. |
Priority
CVSS 3 base score: 7.5
Status
Package | Release | Status |
---|---|---|
libgcrypt20 Launchpad, Ubuntu, Debian |
bionic |
Released
(1.8.1-4ubuntu1.3)
|
focal |
Released
(1.8.5-5ubuntu1.1)
|
|
groovy |
Ignored
(reached end-of-life)
|
|
hirsute |
Released
(1.8.7-2ubuntu2.1)
|
|
impish |
Released
(1.8.7-5ubuntu2)
|
|
jammy |
Released
(1.8.7-5ubuntu2)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(1.8.7-6)
|
|
xenial |
Released
(1.6.5-2ubuntu0.6+esm1)
|
|
Patches: upstream: https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=e8b7f10be275bcedb5fc05ed4837a89bfd605c61 (1.9x) |