CVE-2020-29660: Use After Free

Published Dec 4, 2020
·
Updated

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/ttyio.c and drivers/tty/ttyjobctrl.c may allow a read-after-free attack against TIOCGSID, aka CID-c8bcd9c5be24.

Other sources

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/ttyio.c and drivers/tty/ttyjobctrl.c may allow a read-after-free attack against TIOCGSID.

Reference and upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9

Red Hat

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel. A local user could use this flaw to read numerical value from memory after free.

Affected Software

35 affected componentsFixes available
redhat/kernel-rt<0:4.18.0-348.rt7.130.el8
0:4.18.0-348.rt7.130.el8
redhat/kernel<0:4.18.0-348.el8
0:4.18.0-348.el8
Google Android
Linux Linux kernel<=5.9.13
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Debian Debian Linux=9.0
Debian Debian Linux=10.0
NetApp Active Iq Unified Manager Vmware Vsphere
Broadcom Fabric Operating System
All of the following
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
All of the following
NetApp H410c Firmware
NetApp H410c
All of the following
NetApp A700s Firmware
NetApp A700s
All of the following
NetApp 8300 Firmware
NetApp 8300
All of the following
NetApp 8700 Firmware
NetApp 8700
All of the following
NetApp A400 Firmware
NetApp A400
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
NetApp H410c Firmware
NetApp H410c
NetApp A700s Firmware
NetApp A700s
NetApp 8300 Firmware
NetApp 8300
NetApp 8700 Firmware
NetApp 8700
NetApp A400 Firmware
NetApp A400
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

Dec 4, 2020
CVE Published
12:00 AM
Dec 9, 2020
CVE Published
via MITRE·04:57 PM
Data Sourced
via MITRE·04:57 PM
Description
Dec 10, 2020
Data Sourced
via Red Hat·05:36 PM
DescriptionSeverityAffected Software
Oct 4, 2021
Data Sourced
via Android·12:00 AM
SeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:50 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:24 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2020-29660?

CVE-2020-29660 is considered a medium-severity vulnerability that can lead to read-after-free attacks in the Linux kernel.

2

How do I fix CVE-2020-29660?

To fix CVE-2020-29660, upgrade to kernel versions 0:4.18.0-348.rt7.130.el8 or 0:4.18.0-348.el8 or later.

3

Which Linux kernel versions are affected by CVE-2020-29660?

CVE-2020-29660 affects Linux kernel versions through 5.9.13.

4

Are there any specific distributions impacted by CVE-2020-29660?

Yes, CVE-2020-29660 affects Red Hat, Debian, and various Fedora distributions.

5

What component of the Linux kernel is vulnerable in CVE-2020-29660?

CVE-2020-29660 involves a locking inconsistency issue in the tty subsystem of the Linux kernel.

Contact

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