What is CVE-2026-76886?

CVE-2026-76886 is a high-severity vulnerability in Wireshark, classified under Heap-based Buffer Overflow. CVSS score: 8.1/10. Published 2026-08-19.

How severe is CVE-2026-76886?

High severity. CVSS v3 base score is 8.1 out of 10.

Buffer overflow in Wireshark

CVE-2026-76886

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

Vulnerability class: Buffer Overflow

Published 2026-08-19 · last modified 2026-08-28.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (29.9th percentile), scored 2026-10-05.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

CWE-122 — Heap-based Buffer Overflow

References

www.wireshark.org/security/wnpa-sec-2026-75.html (Vendor Advisory)
gitlab.com/wireshark/wireshark/-/work_items/21439 (Exploit, Mitigation, Vendor Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Exploit, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-76886?: CVE-2026-76886 is a high-severity vulnerability in Wireshark, classified under Heap-based Buffer Overflow. CVSS score: 8.1/10. Published 2026-08-19.
How severe is CVE-2026-76886?: High severity. CVSS v3 base score is 8.1 out of 10.