What is CVE-2026-5404?

CVE-2026-5404 is a medium-severity vulnerability in Wireshark, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 4.7/10. Published 2026-05-01.

How severe is CVE-2026-5404?

Medium severity. CVSS v3 base score is 4.7 out of 10.

Buffer overflow in Wireshark

CVE-2026-5404

K12 RF5 file parser crash in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service

Vulnerability class: Buffer Overflow

EPSS: 0.000 (1.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Wireshark
Wireshark Foundation — versions 4.6.0, 4.4.0

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

cve@gitlab.com (Vendor Advisory)
GitLab Issue #21094 (issue-tracking, Exploit, permissions-required, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2026-5404?: CVE-2026-5404 is a medium-severity vulnerability in Wireshark, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 4.7/10. Published 2026-05-01.
How severe is CVE-2026-5404?: Medium severity. CVSS v3 base score is 4.7 out of 10.