CVE-2020-4788: Infoleak

Published Oct 14, 2020
·
Updated

A flaw was found in the Linux kernel. IBM Power9 processors can speculatively operate on data stored in the L1 cache before it has been completely validated. The attack has limited access to memory and is only able to access memory normally permissible to the execution context. The highest threat from this vulnerability is to data confidentiality.

Other sources

IBM Power9 (AIX 7.1, 7.2, and VIOS 3.1) processors could allow a local user to obtain sensitive information from the data in the L1 cache under extenuating circumstances. IBM X-Force ID: 189296.

IBM Power9 processors could allow a local user to obtain sensitive information from the data in the L1 cache under extenuating circumstances.

IBM

The IBM Power9 processors can speculatively operate on data stored in the L1 cache before it has been completely validated. Unlike other attacks, the attack has limited access to memory and is only able to access memory normally permissable to the execution context. The Power9 systems implement hardware and microcode measures to mitigate unprotected data leakage. An attacker may however induce a condition where the operating system speculative execute instructions using data that the attacker controls. Measuring the timing access of the execution can allow an attacker with a local account to be able to infer memory contents.

Red Hat

Affected Software

37 affected componentsFixes available
redhat/kernel<0:4.18.0-372.9.1.el8
0:4.18.0-372.9.1.el8
IBM AIX<=7.1
IBM AIX<=7.2
IBM VIOS<=3.1
IBM i<=7.1
IBM i<=7.2
IBM i<=7.3
IBM i<=7.4
IBM AIX<=7.1
IBM AIX<=7.2
IBM VIOS<=3.1
All of the following
Any of the following
IBM VIOS=3.1.0
IBM VIOS=3.1.1
IBM VIOS=3.1.2
IBM AIX=7.1.0
IBM AIX=7.1.5
IBM AIX=7.2.0
IBM AIX=7.2.3
IBM AIX=7.2.4
IBM AIX=7.2.5
IBM Power9
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Oracle Communications Cloud Native Core Binding Support Function=22.1.3
Oracle Communications Cloud Native Core Network Exposure Function=22.1.1
Oracle Communications Cloud Native Core Policy=22.2.0
IBM VIOS=3.1.0
IBM VIOS=3.1.1
IBM VIOS=3.1.2
IBM AIX=7.1.0
IBM AIX=7.1.5
IBM AIX=7.2.0
IBM AIX=7.2.3
IBM AIX=7.2.4
IBM AIX=7.2.5
IBM Power9
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1

Remediation

Information

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Event History

Oct 14, 2020
Data Sourced
via Red Hat·08:37 PM
DescriptionSeverityAffected Software
Nov 18, 2020
CVE Published
via IBM·12:00 AM
Nov 19, 2020
Advisory Published
12:00 AM
Nov 20, 2020
CVE Published
via MITRE·03:45 AM
Data Sourced
via MITRE·03:45 AM
DescriptionSeverityWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:51 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:24 AM
RemedyDescriptionSeverityAffected Software
May 6, 2025
Data Sourced
via Debian·04:27 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2020-4788?

CVE-2020-4788 has a high severity rating due to its potential to allow data access through speculative execution vulnerabilities.

2

How do I fix CVE-2020-4788?

To fix CVE-2020-4788, apply the appropriate patches or updates provided by your operating system vendor.

3

Which systems are affected by CVE-2020-4788?

CVE-2020-4788 affects Linux kernel versions up to 0:4.18.0-372.9.1.el8 and certain versions of IBM AIX and VIOS.

4

Can CVE-2020-4788 be exploited remotely?

CVE-2020-4788 requires local access to the affected system for exploitation, limiting its remote attack surface.

5

Is there a workaround for CVE-2020-4788?

While a specific workaround for CVE-2020-4788 is not detailed, it is recommended to apply vendor patches and monitor security bulletins for updates.

Contact

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