The following advisory data is extracted from:
https://access.redhat.com/security/data/csaf/v2/advisories/2024/rhsa-2024_1431.json
Red Hat officially shut down their mailing list notifications October 10, 2023.  Due to this, Packet Storm has recreated the below data as a reference point to raise awareness.  It must be noted that due to an inability to easily track revision updates without crawling Red Hat's archive, these advisories are single notifications and we strongly suggest that you visit the Red Hat provided links to ensure you have the latest information available if the subject matter listed pertains to your environment.
- Packet Storm Staff
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Red Hat Security Advisory
Synopsis:           Moderate: ruby:3.1 security, bug fix, and enhancement update
Advisory ID:        RHSA-2024:1431-03
Product:            Red Hat Enterprise Linux
Advisory URL:       https://access.redhat.com/errata/RHSA-2024:1431
Issue date:         2024-03-19
Revision:           03
CVE Names:          CVE-2021-33621
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Summary: 
An update for the ruby:3.1 module 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:
Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management tasks.
The following packages have been upgraded to a later upstream version: ruby (3.1). (RHEL-28565)
Security Fix(es):
* ruby/cgi-gem: HTTP response splitting in CGI (CVE-2021-33621)
* ruby: ReDoS vulnerability in URI (CVE-2023-28755)
* ruby: ReDoS vulnerability - upstream's incomplete fix for CVE-2023-28755 (CVE-2023-36617)
* ruby: ReDoS vulnerability in Time (CVE-2023-28756)
Bug Fix(es):
* ruby/rubygem-irb: IRB has hard dependency on rubygem-rdoc (RHEL-28569)
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.
Solution:
https://access.redhat.com/articles/11258
CVEs:
CVE-2021-33621
References:
https://access.redhat.com/security/updates/classification/#moderate
https://bugzilla.redhat.com/show_bug.cgi?id=2149706
https://bugzilla.redhat.com/show_bug.cgi?id=2184059
https://bugzilla.redhat.com/show_bug.cgi?id=2184061
https://bugzilla.redhat.com/show_bug.cgi?id=2218614