CVE-2021-39921: Null Pointer Dereference

Published Nov 19, 2021
·
Updated

NULL pointer exception in the Modbus dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file

Affected Software

6 affected componentsFixes available
debian/wireshark
2.6.20-0+deb10u42.6.20-0+deb10u73.4.10-0+deb11u14.0.6-1~deb12u14.0.10-1
Wireshark Wireshark>=3.2.0<=3.2.17
Wireshark Wireshark>=3.4.0<=3.4.9
Fedoraproject Fedora=34
Fedoraproject Fedora=35
Debian Debian Linux=9.0

Event History

Nov 19, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is CVE-2021-39921?

CVE-2021-39921 is a vulnerability in the Modbus dissector in Wireshark that allows denial of service through packet injection or crafted capture file.

2

Which versions of Wireshark are affected by CVE-2021-39921?

Wireshark versions 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 are affected by CVE-2021-39921.

3

How can CVE-2021-39921 be exploited?

CVE-2021-39921 can be exploited by performing packet injection or using a crafted capture file in Wireshark.

4

What is the severity of CVE-2021-39921?

CVE-2021-39921 has a severity rating of high (7.5).

5

How do I fix CVE-2021-39921?

To fix CVE-2021-39921, update Wireshark to version 3.4.10 or higher.

Contact

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