SUSE update for the Linux Kernel (Live Patch 22 for SLE 15)

1) Out-of-bounds write

EUVDB-ID: #VU51549

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-29368

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error when processing untrusted input within the __split_huge_pmd() function in mm/huge_memory.c in the Linux kernel. A local user can abuse the copy-on-write implementation and gain unintended write access because of a race condition in a THP mapcount check.

Mitigation

Update the affected package the Linux Kernel (Live Patch 22 for SLE 15) to the latest version.

Vulnerable software versions

SUSE Linux Enterprise Module for Live Patching: 15-SP1 - 15-SP4

SUSE Linux Enterprise Live Patching: 12-SP4

kgraft-patch-4_12_14-95_68-default: before 2-2.2

kernel-livepatch-4_12_14-150_66-default-debuginfo: before 2-2.2

kernel-livepatch-4_12_14-150_66-default: before 2-2.2

kernel-livepatch-4_12_14-197_83-default: before 2-2.2

CPE2.3

• cpe:2.3:o:suse:suse_linux_enterprise_module_for_live_patching:15-SP1:*:*:*:*:*:*:*
• cpe:2.3:o:suse:suse_linux_enterprise_module_for_live_patching:15-SP4:*:*:*:*:*:*:*
• cpe:2.3:o:suse:suse_linux_enterprise_live_patching:12-SP4:*:*:*:*:*:*:*
• cpe:2.3:a:suse:kgraft-patch-4_12_14-95_68-default:*:*:*:*:*:suse_linux:*:*
• cpe:2.3:a:suse:kernel-livepatch-4_12_14-150_66-default-debuginfo:*:*:*:*:*:suse_linux:*:*
• cpe:2.3:a:suse:kernel-livepatch-4_12_14-150_66-default:*:*:*:*:*:suse_linux:*:*
• cpe:2.3:a:suse:kernel-livepatch-4_12_14-197_83-default:*:*:*:*:*:suse_linux:*:*

External links

https://www.suse.com/support/update/announcement/2021/suse-su-20210864-1/

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.