Ubuntu 20.04 LTS : Linux kernel (OEM) vulnerabilities (USN-5207-1)

critical Nessus Plugin ID 156482

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-5207-1 advisory.

- A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2. (CVE-2021-4001)

- A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the memory pages. A local user could use this flaw to get unauthorized access to some data. (CVE-2021-4002)

- A heap-based buffer overflow flaw was found in the Linux kernel FireDTV media card driver, where the user calls the CA_SEND_MSG ioctl. This flaw allows a local user of the host machine to crash the system or escalate privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability. (CVE-2021-42739)

- An issue was discovered in net/tipc/crypto.c in the Linux kernel before 5.14.16. The Transparent Inter- Process Communication (TIPC) functionality allows remote attackers to exploit insufficient validation of user-supplied sizes for the MSG_CRYPTO message type. (CVE-2021-43267)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected kernel package.

See Also

https://ubuntu.com/security/notices/USN-5207-1

Plugin Details

Severity: Critical

ID: 156482

File Name: ubuntu_USN-5207-1.nasl

Version: 1.9

Type: local

Agent: unix

Published: 1/6/2022

Updated: 1/9/2024

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 8.9

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-43267

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:H/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.10.0-1053-oem

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 1/5/2022

Vulnerability Publication Date: 10/20/2021

Reference Information

CVE: CVE-2021-4001, CVE-2021-4002, CVE-2021-42739, CVE-2021-43267

USN: 5207-1