USN-5091-3: linux-azure Ubuntu

CVSS: UnknownPublished
Published 15-10-2021Last modified 10-02-2026

Vulnerability summary

USN-5091-3 is a vulnerability in linux-azure Ubuntu with no CVSS score yet.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
Not scored
0%100%
No EPSS score yet
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-10-2021
    PublishedVulnerability first disclosed.
  2. 10-02-2026
    Last modifiedVulnerability information updated.

Description

linux-azure, linux-azure-5.4 regression USN-5091-1 fixed vulnerabilities in Linux 5.4-based kernels. Unfortunately, for Linux kernels intended for use within Microsoft Azure environments, that update introduced a regression that could cause the kernel to fail to boot in large Azure instance types. This update fixes the problem. We apologize for the inconvenience. Original advisory details: Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk discovered that the BPF verifier in the Linux kernel missed possible mispredicted branches due to type confusion, allowing a side-channel attack. An attacker could use this to expose sensitive information. (CVE-2021-33624) It was discovered that the tracing subsystem in the Linux kernel did not properly keep track of per-cpu ring buffer state. A privileged attacker could use this to cause a denial of service. (CVE-2021-3679) Alexey Kardashevskiy discovered that the KVM implementation for PowerPC systems in the Linux kernel did not properly validate RTAS arguments in some situations. An attacker in a guest vm could use this to cause a denial of service (host OS crash) or possibly execute arbitrary code. (CVE-2021-37576) It was discovered that the Virtio console implementation in the Linux kernel did not properly validate input lengths in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2021-38160) Michael Wakabayashi discovered that the NFSv4 client implementation in the Linux kernel did not properly order connection setup operations. An attacker controlling a remote NFS server could use this to cause a denial of service on the client. (CVE-2021-38199) It was discovered that the MAX-3421 host USB device driver in the Linux kernel did not properly handle device removal events. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2021-38204)

CVSS metrics

Risk metrics not yet published.

EPSS trend

No EPSS score has been published for this record yet.

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu2 products
  • linux-azure< 5.4.0-1061.64
  • linux-azure-5.4< 5.4.0-1061.64~18.04.1

1 vendor · 2 products

References

2 links