CVE-2021-39926

Name: CVE-2021-39926
Creator: NVD / NIST
Published: 2021-11-19T17:15:08.62+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 7.50%

Last modified Jun 17, 2026

CVE-2021-39926 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Buffer overflow in the Bluetooth HCI_ISO dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file. EPSS estimates a 7.50% chance of exploitation in the next 30 days.

Description

Buffer overflow in the Bluetooth HCI_ISO dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

7.50%

93.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Wireshark	Wireshark	>= 3.4.0, <= 3.4.9
Fedoraproject	Fedora	34
Fedoraproject	Fedora	35
Debian	Debian Linux	10.0
Debian	Debian Linux	11.0

References

https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39926.jsonThird Party Advisory
https://gitlab.com/wireshark/wireshark/-/issues/17649Exploit, Issue Tracking, Patch, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/
https://security.gentoo.org/glsa/202210-04Third Party Advisory
https://www.debian.org/security/2021/dsa-5019Third Party Advisory
https://www.wireshark.org/security/wnpa-sec-2021-08.htmlVendor Advisory
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39926.jsonThird Party Advisory
https://gitlab.com/wireshark/wireshark/-/issues/17649Exploit, Issue Tracking, Patch, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/
https://security.gentoo.org/glsa/202210-04Third Party Advisory
https://www.debian.org/security/2021/dsa-5019Third Party Advisory
https://www.wireshark.org/security/wnpa-sec-2021-08.htmlVendor Advisory

Timeline

Published: Nov 19, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39926?

Buffer overflow in the Bluetooth HCI_ISO dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file

How severe is CVE-2021-39926?

CVE-2021-39926 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 7.50% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39926?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-39926?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST