Red Hat Enterprise Linux 8 update for kpatch-patch

1) Use-after-free

EUVDB-ID: #VU27503

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-19768

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error in the __blk_add_trace() function in kernel/trace/blktrace.c. A local user can run a specially crafted program, trigger a use-after-free error and execute arbitrary code on the system with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

kpatch-patch-4_18_0-147 (Red Hat package): 1-3.el8_1 - 1-4.el8

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 8.1

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 8.1

Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions: 8.1

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions: 8.1

kpatch-patch-4_18_0-147_8_1 (Red Hat package): before 1-2.el8_1

kpatch-patch-4_18_0-147_5_1 (Red Hat package): before 1-4.el8_1

kpatch-patch-4_18_0-147_3_1 (Red Hat package): before 1-9.el8_1

kpatch-patch-4_18_0-147_0_3 (Red Hat package): before 1-9.el8

kpatch-patch-4_18_0-147_0_2 (Red Hat package): before 1-9.el8

External links

http://access.redhat.com/errata/RHSA-2020:2203

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.

2) NULL pointer dereference

EUVDB-ID: #VU28180

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-10711

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the Linux kernel's SELinux subsystem when importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated.

A remote attacker can send specially crafted packets the affected system, trigger a NULL pointer dereference error and crash the Linux kernel.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

kpatch-patch-4_18_0-147 (Red Hat package): 1-3.el8_1 - 1-4.el8

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 8.1

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 8.1

Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions: 8.1

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions: 8.1

kpatch-patch-4_18_0-147_8_1 (Red Hat package): before 1-2.el8_1

kpatch-patch-4_18_0-147_5_1 (Red Hat package): before 1-4.el8_1

kpatch-patch-4_18_0-147_3_1 (Red Hat package): before 1-9.el8_1

kpatch-patch-4_18_0-147_0_3 (Red Hat package): before 1-9.el8

kpatch-patch-4_18_0-147_0_2 (Red Hat package): before 1-9.el8

External links

http://access.redhat.com/errata/RHSA-2020:2203

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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