CVE-2021-36085: Use After Free

Published Jul 1, 2021
·
Updated

SELinux Project SELinux is vulnerable to a denial of service, caused by a use-after-free in cilverifyclassperms. By sending a specially-crafted request, a local attacker could exploit this vulnerability to cause a denial of service condition.

Other sources

The CIL compiler in SELinux 3.2 has a use-after-free in cilverifyclassperms (called from verifymappermclassperms and hashtabmap).

Affected Software

5 affected componentsFixes available
IBM QRadar SIEM<=7.5.0 GA
IBM QRadar SIEM<=7.4.3 GA - 7.4.3 FP4
IBM QRadar SIEM<=7.3.3 GA - 7.3.3 FP10
SELinux Project SELinux=3.2
Fedoraproject Fedora=35

Event History

Jul 1, 2021
CVE Published
via MITRE·02:49 AM
Data Sourced
via MITRE·02:49 AM
Description
Data Sourced
via NVD·03:15 AM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-36085?

CVE-2021-36085 is a vulnerability in SELinux Project SELinux that allows a local attacker to cause a denial of service.

2

What is the severity of CVE-2021-36085?

CVE-2021-36085 has a severity rating of 6.2 (Medium).

3

How can CVE-2021-36085 be exploited?

CVE-2021-36085 can be exploited by sending a specially-crafted request to trigger a use-after-free vulnerability in __cil_verify_classperms.

4

Which software is affected by CVE-2021-36085?

IBM QRadar SIEM versions 7.5.0 GA, 7.4.3 GA - 7.4.3 FP4, and 7.3.3 GA - 7.3.3 FP10 are affected by CVE-2021-36085.

5

How can I patch the vulnerability CVE-2021-36085?

You can patch the vulnerability by applying the following patches provided by IBM: For QRadar SIEM version 7.5.0 GA: [Patch Link](https://www.ibm.com/support/fixcentral/swg/downloadFixes?parent=IBM%20Security&product=ibm/Other+software/IBM+Security+QRadar+SIEM&release=All&platform=Linux&function=fixId&fixids=7.5.0-QRADAR-QRSIEM-20220215133427&includeRequisites=1&includeSupersedes=0&downloadMethod=http&login=true), For QRadar SIEM version 7.4.3 GA - 7.4.3 FP4: [Patch Link](https://www.ibm.com/support/fixcentral/swg/downloadFixes?parent=IBM%20Security&product=ibm/Other+software/IBM+Security+QRadar+SIEM&release=All&platform=Linux&function=fixId&fixids=7.4.3-QRADAR-QRSIEM-20220307203834&includeRequisites=1&includeSupersedes=0&downloadMethod=http), For QRadar SIEM version 7.3.3 GA - 7.3.3 FP10: [Patch Link](https://www.ibm.com/support/fixcentral/swg/downloadFixes?parent=IBM%20Security&product=ibm/Other+software/IBM+Security+QRadar+Vulnerability+Manager&release=All&platform=All&function=fixId&fixids=7.3.3-QRADAR-QRSIEM-20220318161607&includeRequisites=1&includeSupersedes=0&downloadMethod=http&source=SAR).

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