RHSA-2021:2718 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 8.2 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

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: size_t-to-int conversion vulnerability in the filesystem layer (CVE-2021-33909)
• kernel: use-after-free in net/bluetooth/hci_event.c when destroying an hci_chan (CVE-2021-33034)
• kernel: perf_event_parse_addr_filter memory (CVE-2020-25704)
• kernel: security bypass in certs/blacklist.c and certs/system_keyring.c (CVE-2020-26541)
• kernel: fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent (CVE-2020-35508)

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.

Bug Fix(es):

• RHEL8.2 Snapshot2 - tpm: ibmvtpm: Wait for buffer to be set before proceeding (BZ#1933986)
• fnic crash from invalid request pointer (BZ#1961707)
• [Azure][RHEL8.4] Two Patches Needed To Enable Azure Host Time-syncing in VMs (BZ#1963051)
• RHEL kernel 8.2 and higher are affected by data corruption bug in raid1 arrays using bitmaps. (BZ#1969338)

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

The system must be rebooted for this update to take effect.

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.2 x86_64
• Red Hat Enterprise Linux Server - AUS 8.2 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.2 s390x
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.2 ppc64le
• Red Hat Enterprise Linux Server - TUS 8.2 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.2 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.2 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.2 x86_64
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.2 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 8.2 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.2 aarch64

Fixes

• BZ - 1886285 - CVE-2020-26541 kernel: security bypass in certs/blacklist.c and certs/system_keyring.c
• BZ - 1895961 - CVE-2020-25704 kernel: perf_event_parse_addr_filter memory
• BZ - 1902724 - CVE-2020-35508 kernel: fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent
• BZ - 1961305 - CVE-2021-33034 kernel: use-after-free in net/bluetooth/hci_event.c when destroying an hci_chan
• BZ - 1970273 - CVE-2021-33909 kernel: size_t-to-int conversion vulnerability in the filesystem layer

CVEs

• CVE-2020-25704
• CVE-2020-26541
• CVE-2020-35508
• CVE-2021-33034
• CVE-2021-33909

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/security/vulnerabilities/RHSB-2021-006