RHSA-2021:4451 — Security Advisory
Red Hat Security Advisory: gnutls and nettle security, bug fix, and enhancement update
Severity
ModerateRed Hat Product Security
Products
Official CSAF product identity
Published · November 10, 2021
Updated · October 14, 2026
Topic
An update for gnutls and nettle 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 gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS.
Nettle is a cryptographic library that is designed to fit easily in almost any context: In crypto toolkits for object-oriented languages, such as C++, Python, or Pike, in applications like LSH or GNUPG, or even in kernel space.
The following packages have been upgraded to a later upstream version: gnutls (3.6.16). (BZ#1956783)
Security Fix(es):
-
nettle: Remote crash in RSA decryption via manipulated ciphertext (CVE-2021-3580)
-
gnutls: Use after free in client key_share extension (CVE-2021-20231)
-
gnutls: Use after free in client_send_params in lib/ext/pre_shared_key.c (CVE-2021-20232)
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.