Buffer overflow in Wireshark

CVE-2026-5402

TLS protocol dissector heap overflow in Wireshark 4.6.0 to 4.6.4 allows denial of service and possible code execution

Vulnerability class: Buffer Overflow

EPSS: 0.000 (13.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Wireshark
Wireshark Foundation — versions 4.6.0

Weakness classification (CWE)

CWE-122 — Heap-based Buffer Overflow

References

cve@gitlab.com (Vendor Advisory)
GitLab Issue #21090 (issue-tracking, Exploit, permissions-required, Issue Tracking)

Frequently asked questions

What is CVE-2026-5402?: CVE-2026-5402 is a high-severity vulnerability in Wireshark, classified under Heap-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-04-30.
How severe is CVE-2026-5402?: High severity. CVSS v3 base score is 8.8 out of 10.