RHSA-2020:5430 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 7.4 Advanced Update Support, Red Hat Enterprise Linux 7.4 Telco Extended Update Support, and Red Hat Enterprise Linux 7.4 Update Services for SAP Solutions.

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

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

Security Fix(es):

• kernel: out of bounds write in function i2c_smbus_xfer_emulated in drivers/i2c/i2c-core-smbus.c (CVE-2017-18551)
• kernel: out of bounds write in i2c driver leads to local escalation of privilege (CVE-2019-9454)
• kernel: mounting a crafted ext4 filesystem image, performing some operations, and unmounting can lead to a use-after-free in ext4_put_super in fs/ext4/super.c (CVE-2019-19447)
• kernel: out-of-bounds write via crafted keycode table (CVE-2019-20636)
• kernel: sg_write function lacks an sg_remove_request call in a certain failure case (CVE-2020-12770)

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):

• Secure boot key is not loaded with kernel-3.10.0-1159.el7: MODSIGN: Couldn't get UEFI MokListRT (BZ#1876951)
• RHEL7.6: no-carrier configured interfaces causes soft lockups by mount.nfs and hang booting/shutdown process (BZ#1889770)
• [Intel Bug]: hrtimer (rdmavt RNR timer) was lost sometimes (BZ#1892996)

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 Server - AUS 7.4 x86_64
• Red Hat Enterprise Linux Server - TUS 7.4 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.4 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.4 x86_64

Fixes

• BZ - 1757368 - CVE-2017-18551 kernel: out of bounds write in function i2c_smbus_xfer_emulated in drivers/i2c/i2c-core-smbus.c
• BZ - 1781679 - CVE-2019-19447 kernel: mounting a crafted ext4 filesystem image, performing some operations, and unmounting can lead to a use-after-free in ext4_put_super in fs/ext4/super.c
• BZ - 1818818 - CVE-2019-9454 kernel: out of bounds write in i2c driver leads to local escalation of privilege
• BZ - 1824059 - CVE-2019-20636 kernel: out-of-bounds write via crafted keycode table
• BZ - 1834845 - CVE-2020-12770 kernel: sg_write function lacks an sg_remove_request call in a certain failure case

CVEs

• CVE-2017-18551
• CVE-2019-9454
• CVE-2019-19447
• CVE-2019-20636
• CVE-2020-12770

References

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