RHSA-2021:4409 - Security Advisory

Topic

An update for libgcrypt is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The libgcrypt library provides general-purpose implementations of various cryptographic algorithms.

Security Fix(es):

• libgcrypt: mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm (CVE-2021-33560)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for ARM 64 8 aarch64

Fixes

• BZ - 1970096 - CVE-2021-33560 libgcrypt: mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm
• BZ - 1976137 - Enable hardware optimizations in FIPS mode

CVEs

• CVE-2021-33560

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.5_release_notes/