What is CVE-2026-0959?

CVE-2026-0959 is a medium-severity vulnerability in Wireshark, classified under Out-of-bounds Write. CVSS score: 5.3/10. Published 2026-01-14.

How severe is CVE-2026-0959?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Buffer overflow in Wireshark

CVE-2026-0959

IEEE 802.11 protocol dissector crash in Wireshark 4.6.0 to 4.6.2 and 4.4.0 to 4.4.12 allows denial of service

Vulnerability class: Buffer Overflow

Published 2026-01-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (10.0th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Wireshark
Wireshark Foundation — versions 4.6.0, 4.4.0

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

www.wireshark.org/security/wnpa-sec-2026-02.html (Vendor Advisory)
gitlab.com/wireshark/wireshark/-/issues/20939 (issue-tracking, permissions-required, Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2026-0959?: CVE-2026-0959 is a medium-severity vulnerability in Wireshark, classified under Out-of-bounds Write. CVSS score: 5.3/10. Published 2026-01-14.
How severe is CVE-2026-0959?: Medium severity. CVSS v3 base score is 5.3 out of 10.