Red Hat Enterprise Linux Server 7.6 update for kpatch-patch

Published: 2021-10-13 | Updated: 2023-08-29

Risk	Medium
Patch available	YES
Number of vulnerabilities	3
CVE-ID	CVE-2021-22543 CVE-2021-22555 CVE-2021-37576
CWE-ID	CWE-119 CWE-787
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available. Vulnerability #2 is being exploited in the wild.
Vulnerable software Subscribe	kpatch-patch-3_10_0-957_78_2 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_76_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_72_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_70_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_66_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_65_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_62_1 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_61_2 (Red Hat package) Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_61_1 (Red Hat package) Operating systems & Components / Operating system package or component Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions Operating systems & Components / Operating system package or component Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions Operating systems & Components / Operating system package or component kpatch-patch-3_10_0-957_80_1 (Red Hat package) Operating systems & Components / Operating system package or component Red Hat Enterprise Linux Server - AUS Operating systems & Components / Operating system
Vendor	Red Hat Inc.

Security Bulletin

This security bulletin contains information about 3 vulnerabilities.

1) Buffer overflow

EUVDB-ID: #VU56018

Risk: Low

CVSSv3.1:

CVE-ID: CVE-2021-22543

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

Description

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

The vulnerability exists due to a boundary error in Linux kernel when handling VM_IO|VM_PFNMAP vmas in KVM. A local user can can bypass RO checks and cause the pages to get freed while still accessible by the VMM and guest. As a result, an attacker with the ability to start and control a VM to read/write random pages of memory, can trigger memory corruption and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

kpatch-patch-3_10_0-957_78_2 (Red Hat package): 1-1.el7

kpatch-patch-3_10_0-957_76_1 (Red Hat package): 1-1.el7 - 1-2.el7

kpatch-patch-3_10_0-957_72_1 (Red Hat package): 1-1.el7 - 1-2.el7

kpatch-patch-3_10_0-957_70_1 (Red Hat package): 1-2.el7 - 1-4.el7

kpatch-patch-3_10_0-957_66_1 (Red Hat package): 1-1.el7 - 1-5.el7

kpatch-patch-3_10_0-957_65_1 (Red Hat package): 1-1.el7 - 1-5.el7

kpatch-patch-3_10_0-957_62_1 (Red Hat package): 1-1.el7 - 1-5.el7

kpatch-patch-3_10_0-957_61_2 (Red Hat package): 1-1.el7 - 1-5.el7

kpatch-patch-3_10_0-957_61_1 (Red Hat package): 1-1.el7 - 1-5.el7

Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions: 7.6

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions: 7.6

Red Hat Enterprise Linux Server - AUS: 7.6

kpatch-patch-3_10_0-957_80_1 (Red Hat package): before 1-1.el7

CPE2.3

cpe:2.3:o:red_hat:kpatch-patch-3_10_0-957_78_2:1-1.el7:*:*:*:*:red_hat_enterprise_linux:*:*

External links

http://access.redhat.com/errata/RHSA-2021:3814

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?

2) Out-of-bounds write

EUVDB-ID: #VU56017

Risk: Low

CVSSv3.1:

CVE-ID: CVE-2021-22555

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

Exploit availability: Yes

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 in net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.