SB2021032008 - Ubuntu update for linux-oem-5.10



SB2021032008 - Ubuntu update for linux-oem-5.10

Published: March 20, 2021

Security Bulletin ID SB2021032008
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Heap-based buffer overflow (CVE-ID: CVE-2021-20194)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


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

The vulnerability exists due to a boundary error within the __cgroup_bpf_run_filter_getsockopt() function, when kernel is compiled with config params CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY not set, and BPF hook to getsockopt is registered. A local user can trigger a heap-based buffer overflow and execute arbitrary code with elevated privileges.


2) Use-after-free (CVE-ID: CVE-2021-3347)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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


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

The vulnerability exists due to a use-after-free error when handling PI futexes. A local user can run a specially crafted program to trigger a use-after-free error and execute arbitrary code with elevated privileges.



3) Use-after-free (CVE-ID: CVE-2021-3348)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


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

The vulnerability exists due to a use-after-free error within the nbd_add_socket in drivers/block/nbd.c. A local authenticated user can trigger a use-after-free error and escalate privileges on the system.


Remediation

Install update from vendor's website.