Red Hat Enterprise Linux 7 update for kernel

1) Use-after-free

EUVDB-ID: #VU58332

Risk: Low

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

CVE-ID: CVE-2020-36385

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 drivers/infiniband/core/ucma.c, because the ctx is reached via the ctx_list in some ucma_migrate_id situations where ucma_close is called. A local user can run a specially crafted program to trigger the use-after-free error and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

kernel (Red Hat package): 3.10.0-123.1.2.el7 - 3.10.0-1160.45.1.el7

Red Hat Enterprise Linux for Power, little endian: 7

Red Hat Enterprise Linux for Power, big endian: 7

Red Hat Enterprise Linux for IBM z Systems: 7

Red Hat Enterprise Linux for Scientific Computing: 7

Red Hat Enterprise Linux Desktop: 7

Red Hat Enterprise Linux Workstation: 7

Red Hat Enterprise Linux Server: 7

External links

http://access.redhat.com/errata/RHSA-2021:4777

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.