SB2022020337 - Ubuntu update for linux

Description

This security bulletin contains information about 3 vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2021-3640)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/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 use-after-free error in sco_sock_sendmsg() function of the Linux kernel HCI subsystem. A privileged local user can call ioct UFFDIO_REGISTER or other way trigger race condition to escalate privileges on the system.

2) Use-after-free (CVE-ID: CVE-2021-3752)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:A/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 remote attacker to escalate privileges on the system.

The vulnerability exists due to a use-after-free error in the Linux kernel’s Bluetooth subsystem when a user calls connect to the socket and disconnect simultaneously. A local user can escalate privileges on the system.

3) Buffer overflow (CVE-ID: CVE-2021-42739)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/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 within the firewire subsystem in the Linux kernel in drivers/media/firewire/firedtv-avc.c and drivers/media/firewire/firedtv-ci.c files. A local privileged user can run a specially crafted program tat calls avc_ca_pmt() function to trigger memory corruption and execute arbitrary code with elevated privileges.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-5267-1