CVE-2020-27171: Medium severity linux kernel vulnerability

Published Mar 20, 2021
·
Updated

An issue was discovered in the Linux kernel before 5.11.8. kernel/bpf/verifier.c has an off-by-one error (with a resultant integer underflow) affecting out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory, aka CID-10d2bb2e6b1d.

Affected Software

10 affected componentsFixes available
Linux Linux kernel<5.11.8
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Debian Debian Linux=9.0
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=20.04
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.22-16.12.25-1

Event History

Mar 20, 2021
CVE Published
via MITRE·09:41 PM
Data Sourced
via MITRE·09:41 PM
Description
Jan 11, 2024
Data Sourced
via Launchpad·11:47 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·03:44 AM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2020-27171?

CVE-2020-27171 is considered critical due to its potential to enable side-channel attacks that can bypass mitigations for Spectre vulnerabilities.

2

How do I fix CVE-2020-27171?

To fix CVE-2020-27171, update the Linux kernel to version 5.11.8 or later, or apply available patches for affected distributions.

3

Which Linux distributions are affected by CVE-2020-27171?

CVE-2020-27171 affects multiple distributions including Fedora, Debian, and Ubuntu versions prior to their respective security updates.

4

What kind of vulnerability is CVE-2020-27171?

CVE-2020-27171 is an off-by-one error in the Linux kernel's BPF verifier that can lead to integer underflow and side-channel attacks.

5

What is the potential impact of CVE-2020-27171?

The potential impact of CVE-2020-27171 includes unauthorized access to sensitive information through process memory exposure.

Contact

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