RHSA-2020:3952 - Security Advisory

Topic

An update for expat is now available for Red Hat Enterprise Linux 7.

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

Expat is a C library for parsing XML documents.

Security Fix(es):

• expat: large number of colons in input makes parser consume high amount of resources, leading to DoS (CVE-2018-20843)
• expat: heap-based buffer over-read via crafted XML input (CVE-2019-15903)

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 7.9 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

After installing the updated packages, applications using the Expat library must be restarted for the update to take effect.

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le

Fixes

• BZ - 1723723 - CVE-2018-20843 expat: large number of colons in input makes parser consume high amount of resources, leading to DoS
• BZ - 1752592 - CVE-2019-15903 expat: heap-based buffer over-read via crafted XML input

CVEs

• CVE-2018-20843
• CVE-2019-15903

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/7.9_release_notes/index