CVE-2021-33640: Use After Free

Published Dec 19, 2022
·
Updated

After tarclose(), libtar.c releases the memory pointed to by pointer t. After tarclose() is called in the list() function, it continues to use pointer t: freelonglinklongname(t->thbuf) . As a result, the released memory is used (use-after-free).

Affected Software

8 affected components
Huawei Openeuler=20.03-sp1
Huawei Openeuler=20.03-sp2
Huawei Openeuler=22.03
Fedoraproject Fedora=36
Fedoraproject Fedora=37
Openatom Openeuler=20.03-sp1
Openatom Openeuler=20.03-sp2
Openatom Openeuler=22.03

Event History

Dec 19, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-33640?

CVE-2021-33640 is a vulnerability in the libtar.c library that allows for the use of released memory, resulting in a use-after-free scenario.

2

How severe is CVE-2021-33640?

CVE-2021-33640 has a severity rating of 9.8 (Critical).

3

Which software versions are affected by CVE-2021-33640?

CVE-2021-33640 affects Huawei Openeuler 20.03 SP1 and SP2, Huawei Openeuler 22.03, and Fedoraproject Fedora 36 and 37.

4

How can I fix CVE-2021-33640?

To fix CVE-2021-33640, update your affected software to a version that includes the necessary patches and security fixes.

5

Where can I find more information about CVE-2021-33640?

More information about CVE-2021-33640 can be found at the following references: [Link 1](https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/), [Link 2](https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/), [Link 3](https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2021-33640&packageName=libtar)

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