Vulnerabilities
Misconfiguration
Compliance
Cryptography
CVE Vulnerabilities

CVE-2021-39920

NULL Pointer Dereference

Published: Nov 18, 2021 | Modified: Jun 17, 2026
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
7.5 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Ubuntu
LOW
Vulnerability-free packages from our partners
Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-39920
CWEhttps://cwe.mitre.org/data/definitions/476.html

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

Weakness

The product dereferences a pointer that it expects to be valid but is NULL.

Affected Software

NameVendorStart VersionEnd Version
WiresharkWireshark3.4.0 (including)3.4.10 (excluding)
WiresharkUbuntubionic*
WiresharkUbuntudevel*
WiresharkUbuntuesm-apps/focal*
WiresharkUbuntuesm-apps/jammy*
WiresharkUbuntuesm-apps/noble*
WiresharkUbuntuesm-apps/resolute*
WiresharkUbuntuesm-apps/xenial*
WiresharkUbuntufocal*
WiresharkUbuntuhirsute*
WiresharkUbuntuimpish*
WiresharkUbuntujammy*
WiresharkUbuntukinetic*
WiresharkUbuntulunar*
WiresharkUbuntumantic*
WiresharkUbuntunoble*
WiresharkUbuntuoracular*
WiresharkUbuntuplucky*
WiresharkUbuntuquesting*
WiresharkUbunturesolute*
WiresharkUbuntustonking*
WiresharkUbuntutrusty*
WiresharkUbuntutrusty/esm*
WiresharkUbuntuxenial*

Potential Mitigations

References

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