Ubuntu 20.04 : Linux kernel regression (USN-4367-2)

high Nessus Plugin ID 136965
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Ubuntu host is missing one or more security-related patches.

Description

USN-4367-1 fixed vulnerabilities in the 5.4 Linux kernel.
Unfortunately, that update introduced a regression in overlayfs. This update corrects the problem.

We apologize for the inconvenience.

It was discovered that the btrfs implementation in the Linux kernel did not properly detect that a block was marked dirty in some situations. An attacker could use this to specially craft a file system image that, when unmounted, could cause a denial of service (system crash). (CVE-2019-19377)

It was discovered that the linux kernel did not properly validate certain mount options to the tmpfs virtual memory file system. A local attacker with the ability to specify mount options could use this to cause a denial of service (system crash). (CVE-2020-11565)

It was discovered that the block layer in the Linux kernel contained a race condition leading to a use-after-free vulnerability. A local attacker could possibly use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2020-12657).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected packages.

See Also

https://usn.ubuntu.com/4367-2/

Plugin Details

Severity: High

ID: 136965

File Name: ubuntu_USN-4367-2.nasl

Version: 1.4

Type: local

Agent: unix

Published: 5/29/2020

Updated: 12/28/2020

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

CVSS Score Source: CVE-2019-19377

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-osp1, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual, cpe:/o:canonical:ubuntu_linux:20.04

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

Exploit Ease: No known exploits are available

Patch Publication Date: 5/28/2020

Vulnerability Publication Date: 11/29/2019

Reference Information

CVE: CVE-2019-19377, CVE-2020-11565, CVE-2020-12657

USN: 4367-2