CVE-2021-33560

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.57%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory gnupg.org Vendor Advisory gnupg.org Vendor Advisory gnupg.org Vendor Advisory gnupg.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://dev.gnupg.org/T5328 vendor advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00021.html third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7OAPCUGPF3VLA7QAJUQSL255D4ITVTL/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BKKTOIGFW2SGN3DO2UHHVZ7MJSYN4AAB/ vendor advisory
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory
https://dev.gnupg.org/T5466 release notes vendor advisory
https://dev.gnupg.org/T5305 release notes vendor advisory
https://dev.gnupg.org/rCe8b7f10be275bcedb5fc05ed4837a89bfd605c61 patch vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html third party advisory patch
https://www.oracle.com/security-alerts/cpuapr2022.html third party advisory patch
https://www.oracle.com/security-alerts/cpujul2022.html third party advisory patch
https://security.gentoo.org/glsa/202210-13 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-33560?
CVE-2021-33560 has been scored as a high severity vulnerability.
How to fix CVE-2021-33560?
To fix CVE-2021-33560, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-33560 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-33560 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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