USN-5647-1: Linux kernel (GCP) vulnerabilities
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) Moshe Kol, Amit Klein and Yossi Gilad discovered that the IP implementation in the Linux kernel did not provide sufficient randomization when calculating port offsets. An attacker could possibly use this to expose sensitive information. (CVE-2022-1012, CVE-2022-32296) Norbert Slusarek discovered that a race condition existed in the perf subsystem in the Linux kernel, resulting in a use-after-free vulnerability. A privileged local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2022-1729) It was discovered that the device-mapper verity (dm-verity) driver in the Linux kernel did not properly verify targets being loaded into the device- mapper table. A privileged attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2022-2503) 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
Event History
Child vulnerabilities
Contains the following vulnerabilities.
Frequently Asked Questions
What is the vulnerability ID for this advisory?
The vulnerability ID for this advisory is CVE-2021-33655.
What is the severity of CVE-2021-33655?
The severity of CVE-2021-33655 is not specified in the advisory.
How can an attacker exploit CVE-2021-33655?
An attacker can exploit CVE-2021-33655 by using an out-of-bounds write to cause a system crash or execute arbitrary code.
Which software versions are affected by this vulnerability?
The affected software versions are linux-image-gcp-lts-20.04 (version 5.4.0.1089.94) and linux-image-5.4.0-1089-gcp (version 5.4.0-1089.97).
How can I fix CVE-2021-33655?
To fix CVE-2021-33655, update the linux-image-gcp-lts-20.04 package to version 5.4.0.1089.94 or higher, and update the linux-image-5.4.0-1089-gcp package to version 5.4.0-1089.97 or higher.