RHSA-2023:6021 - Security Advisory

Topic

An update for the varnish:6 module is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Telecommunications Update Service, and Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions.

Red Hat Product Security has rated this update as having a security impact of Important. 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

Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't have to create the same web page over and over again, giving the website a significant speed up.

Security Fix(es):

• HTTP/2: Multiple HTTP/2 enabled web servers are vulnerable to a DDoS attack (Rapid Reset Attack) (CVE-2023-44487)

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

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 - Extended Update Support Extension 8.4 x86_64
• Red Hat Enterprise Linux Server - AUS 8.4 x86_64
• Red Hat Enterprise Linux Server - TUS 8.4 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.4 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.4 x86_64

Fixes

• BZ - 2242803 - CVE-2023-44487 HTTP/2: Multiple HTTP/2 enabled web servers are vulnerable to a DDoS attack (Rapid Reset Attack)

CVEs

• CVE-2023-44487

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/security/vulnerabilities/RHSB-2023-003