Vulnerability · Published Apr 30, 2026 · Assigned by GitLab
CVE-2026-5402Heap-based Buffer Overflow in Wireshark
High 8.8
In plain English
A high-severity heap buffer overflow in Wireshark from Wireshark Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.4%top 66.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
TLS protocol dissector heap overflow in Wireshark 4.6.0 to 4.6.4 allows denial of service and possible code execution
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | wireshark | 4.6.5-1 | DEBIAN-CVE-2026-5402 |
| Ubuntu:25.10 | wireshark | no fix listed | UBUNTU-CVE-2026-5402 |
| Ubuntu:26.04:LTS | wireshark | no fix listed | UBUNTU-CVE-2026-5402 |
| Ubuntu:26.10 | wireshark | no fix listed | UBUNTU-CVE-2026-5402 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Wireshark Foundation | Wireshark | 4.6.0 – before 4.6.5 |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
- https://www.wireshark.org/security/wnpa-sec-2026-14.html
- GitLab Issue #21090 issue-tracking, permissions-required
- https://access.redhat.com/security/cve/CVE-2026-5402 vdb-entry, x_refsource_REDHAT
- RHBZ#2464038 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5402.json x_sadp-csaf-vex