Moderate: varnish:6 security, bug fix, and enhancement update

Synopsis

Moderate: varnish:6 security, bug fix, and enhancement update

Type/Severity

Security Advisory: Moderate

Topic

An update for the varnish:6 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

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.

The following packages have been upgraded to a later upstream version: varnish (6.0.6). (BZ#1795673)

Security Fix(es):

• varnish: denial of service handling certain crafted HTTP/1 requests (CVE-2019-15892)
  
• varnish: remote clients may cause Varnish to assert and restart which could result in DoS (CVE-2020-11653)
  
• varnish: not clearing pointer between two client requests leads to information disclosure (CVE-2019-20637)
  

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 8.3 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 - 1756079 - CVE-2019-15892 varnish: denial of service handling certain crafted HTTP/1 requests
• BZ - 1772362 - CVE-2019-20637 varnish: not clearing pointer between two client requests leads to information disclosure
• BZ - 1813867 - CVE-2020-11653 varnish: remote clients may cause Varnish to assert and restart which could result in DoS

CVEs

• CVE-2019-15892
• CVE-2019-20637
• CVE-2020-11653

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.3_release_notes/