RHSA-2020:5441 - Security Advisory

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 7.

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-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

• kernel: metadata validator in XFS may cause an inode with a valid, user-creatable extended attribute to be flagged as corrupt (CVE-2020-14385)
• kernel: The flow_dissector feature allows device tracking (CVE-2019-18282)
• kernel: Buffer over-read in crypto_authenc_extractkeys() when a payload longer than 4 bytes is not aligned. (CVE-2020-10769)
• kernel: buffer uses out of index in ext3/4 filesystem (CVE-2020-14314)
• kernel: umask not applied on filesystem without ACL support (CVE-2020-24394)
• kernel: TOCTOU mismatch in the NFS client code (CVE-2020-25212)
• kernel: improper input validation in ppp_cp_parse_cr function leads to memory corruption and read overflow (CVE-2020-25643)

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):

• kernel-rt: update to the latest RHEL7.9.z2 source tree (BZ#1873318)
• deadlock between handle_mm_fault() and ptep_clear_flush() (BZ#1888872)

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 Real Time 7 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 7 x86_64

Fixes

• BZ - 1708775 - CVE-2020-10769 kernel: Buffer over-read in crypto_authenc_extractkeys() when a payload longer than 4 bytes is not aligned.
• BZ - 1796360 - CVE-2019-18282 kernel: The flow_dissector feature allows device tracking
• BZ - 1853922 - CVE-2020-14314 kernel: buffer uses out of index in ext3/4 filesystem
• BZ - 1869141 - CVE-2020-24394 kernel: umask not applied on filesystem without ACL support
• BZ - 1874800 - CVE-2020-14385 kernel: metadata validator in XFS may cause an inode with a valid, user-creatable extended attribute to be flagged as corrupt
• BZ - 1877575 - CVE-2020-25212 kernel: TOCTOU mismatch in the NFS client code
• BZ - 1879981 - CVE-2020-25643 kernel: improper input validation in ppp_cp_parse_cr function leads to memory corruption and read overflow
• BZ - 1888872 - deadlock between handle_mm_fault() and ptep_clear_flush() [rhel-7.9.z]

CVEs

• CVE-2019-18282
• CVE-2020-10769
• CVE-2020-14314
• CVE-2020-14385
• CVE-2020-24394
• CVE-2020-25212
• CVE-2020-25643

References

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