High severity · published Nov 19, 2021
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
7.5
CVSS
8%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)8.0% · higher than 95% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WI
Wireshark · Wireshark Foundation
>=3.4.0, <3.4.10 · source: vendor, NVD
DL
Debian Linux · Debian
10.0; 11.0 · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-39926
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39926
Third Party Advisory
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39926.json
Exploit
https://gitlab.com/wireshark/wireshark/-/issues/17649
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/
Third Party Advisory
https://security.gentoo.org/glsa/202210-04
Third Party Advisory
https://www.debian.org/security/2021/dsa-5019
More from Wireshark
9.8
CVE-2026-76886
Heap-based Buffer Overflow in Wireshark
9.8
CVE-2022-0582
Unaligned access in the CSN.1 protocol dissector in Wireshark 3.6.0 to 3.6.1 and 3.4.0 to 3.4.11 allows denial of service via packet injection or crafted capture file
8.8
CVE-2026-95387
Heap-based Buffer Overflow in Wireshark
8.8
CVE-2026-5402
Heap-based Buffer Overflow in Wireshark
8.1
CVE-2026-95389
Heap-based Buffer Overflow in Wireshark