RHSA-2021:3044 - Security Advisory

Topic

An update for kpatch-patch is now available for Red Hat Enterprise Linux 8.

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: Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks (CVE-2021-22543)
• kernel: out-of-bounds write in xt_compat_target_from_user() in net/netfilter/x_tables.c (CVE-2021-22555)

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 8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.4 x86_64
• Red Hat Enterprise Linux Server - AUS 8.4 x86_64
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.4 ppc64le
• Red Hat Enterprise Linux Server - TUS 8.4 x86_64
• Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 8.4 ppc64le
• Red Hat Enterprise Linux Server - Update Services for SAP Solutions 8.4 x86_64

Fixes

• BZ - 1965461 - CVE-2021-22543 kernel: Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks
• BZ - 1971651 - CVE-2021-3609 kernel: race condition in net/can/bcm.c leads to local privilege escalation
• BZ - 1980101 - CVE-2021-22555 kernel: out-of-bounds write in xt_compat_target_from_user() in net/netfilter/x_tables.c

CVEs

• CVE-2021-3609
• CVE-2021-22543
• CVE-2021-22555

References

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