CVE-2021-39921

Public Exploit

Description

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

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.18%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory wireshark.org
Affected: Wireshark Foundation Wireshark
Published at:
Updated at:

References

Link Tags
https://www.wireshark.org/security/wnpa-sec-2021-14.html vendor advisory
https://gitlab.com/wireshark/wireshark/-/issues/17703 patch exploit third party advisory issue tracking
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39921.json third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/ vendor advisory
https://www.debian.org/security/2021/dsa-5019 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00015.html third party advisory mailing list
https://security.gentoo.org/glsa/202210-04 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-39921?
CVE-2021-39921 has been scored as a high severity vulnerability.
How to fix CVE-2021-39921?
To fix CVE-2021-39921, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39921 being actively exploited in the wild?
It is possible that CVE-2021-39921 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39921?
CVE-2021-39921 affects Wireshark Foundation Wireshark.
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