USN-5580-1: Linux kernel (AWS) vulnerabilities

Published Aug 24, 2022
·
Updated

It was discovered that the framebuffer driver on the Linux kernel did not verify size limits when changing font or screen size, leading to an out-of- bounds write. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-33655) It was discovered that the virtual terminal driver in the Linux kernel did not properly handle VGA console font changes, leading to an out-of-bounds write. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-33656) It was discovered that the Packet network protocol implementation in the Linux kernel contained an out-of-bounds access. A remote attacker could use this to expose sensitive information (kernel memory). (CVE-2022-20368) Domingo Dirutigliano and Nicola Guerrera discovered that the netfilter subsystem in the Linux kernel did not properly handle rules that truncated packets below the packet header size. When such rules are in place, a remote attacker could possibly use this to cause a denial of service (system crash). (CVE-2022-36946)

Affected Software

1 affected component
Canonical Linux kernel (AWS)

Event History

May 10, 2025
Advisory Published
via Ubuntu·03:53 AM
Data Sourced
via Ubuntu·03:53 AM
DescriptionAffected Software

Child vulnerabilities

Contains the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2021-33655?

The severity of CVE-2021-33655 is high.

2

How can a local attacker exploit CVE-2021-33655?

A local attacker can exploit CVE-2021-33655 by causing a denial of service (system crash) or possibly executing arbitrary code.

3

Which Linux kernel versions are affected by CVE-2021-33655?

The Linux kernel versions affected by CVE-2021-33655 include linux-image-4.4.0-1150-aws and linux-image-aws.

4

How can I fix the vulnerability CVE-2021-33655?

To fix the vulnerability CVE-2021-33655, update the linux-image-4.4.0-1150-aws and linux-image-aws packages to version 4.4.0-1150.165 or higher.

5

Where can I find more information about CVE-2021-33655?

You can find more information about CVE-2021-33655 on the Ubuntu Security Advisory at https://ubuntu.com/security/CVE-2021-33655.

Contact

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