CVE-2021-33560

2021-06-0800:00:00

ubuntu.com

0.002 Low

EPSS

Percentile

60.9%

JSON

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.

Bugs

<https://dev.gnupg.org/T5328>

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.

OSVersionArchitecturePackageVersionFilename
ubuntu18.04noarchlibgcrypt20< 1.8.1-4ubuntu1.3UNKNOWN
ubuntu20.04noarchlibgcrypt20< 1.8.5-5ubuntu1.1UNKNOWN
ubuntu21.04noarchlibgcrypt20< 1.8.7-2ubuntu2.1UNKNOWN
ubuntu21.10noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu22.04noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu22.10noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu23.04noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu23.10noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu24.04noarchlibgcrypt20< 1.8.7-5ubuntu2UNKNOWN
ubuntu16.04noarchlibgcrypt20< 1.6.5-2ubuntu0.6+esm1UNKNOWN

OS	Version	Architecture	Package	Version	Filename
ubuntu	18.04	noarch	libgcrypt20	< 1.8.1-4ubuntu1.3	UNKNOWN
ubuntu	20.04	noarch	libgcrypt20	< 1.8.5-5ubuntu1.1	UNKNOWN
ubuntu	21.04	noarch	libgcrypt20	< 1.8.7-2ubuntu2.1	UNKNOWN
ubuntu	21.10	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	22.04	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	22.10	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	23.04	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	23.10	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	24.04	noarch	libgcrypt20	< 1.8.7-5ubuntu2	UNKNOWN
ubuntu	16.04	noarch	libgcrypt20	< 1.6.5-2ubuntu0.6+esm1	UNKNOWN