RHSA-2021:3442 - Security Advisory

Topic

An update is now available for Red Hat Enterprise Linux 8.1 Extended Update Support.

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

This is a kernel live patch module which is automatically loaded by the RPM post-install script to modify the code of a running kernel.

Security Fix(es):

• kernel: race condition in net/can/bcm.c leads to local privilege escalation (CVE-2021-3609)
• kernel: use-after-free in route4_change() in net/sched/cls_route.c (CVE-2021-3715)
• kernel: powerpc: KVM guest OS users can cause host OS memory corruption (CVE-2021-37576)

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 8.1 x86_64
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.1 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.1 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.1 x86_64

Fixes

• BZ - 1971651 - CVE-2021-3609 kernel: race condition in net/can/bcm.c leads to local privilege escalation
• BZ - 1986506 - CVE-2021-37576 kernel: powerpc: KVM guest OS users can cause host OS memory corruption
• BZ - 1993988 - CVE-2021-3715 kernel: use-after-free in route4_change() in net/sched/cls_route.c

CVEs

• CVE-2021-3609
• CVE-2021-3715
• CVE-2021-37576

References

• https://access.redhat.com/security/updates/classification/#important