CVE-2021-39923

Description

Large loop in the PNRP 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 1.58% Top 20%
Vendor Advisory debian.org Vendor Advisory gitlab.com Vendor Advisory wireshark.org
Affected: Wireshark Foundation Wireshark
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39923.json third party advisory
https://www.wireshark.org/security/wnpa-sec-2021-11.html vendor advisory
https://gitlab.com/wireshark/wireshark/-/issues/17684 issue tracking patch 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

Frequently Asked Questions

What is the severity of CVE-2021-39923?
CVE-2021-39923 has been scored as a high severity vulnerability.
How to fix CVE-2021-39923?
To fix CVE-2021-39923, 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-2021-39923 being actively exploited in the wild?
It is possible that CVE-2021-39923 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39923?
CVE-2021-39923 affects Wireshark Foundation Wireshark.
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