CVE-2026-5402
Published: 30 April 2026
Summary
CVE-2026-5402 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Wireshark Wireshark. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Malicious File (T1204.002); ranked at the 11.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-16 (Memory Protection) and SI-2 (Flaw Remediation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly mandates timely patching of the heap overflow vulnerability in Wireshark versions 4.6.0-4.6.4 as described in the Wireshark security advisory.
Implements memory protections like ASLR, DEP, and heap canaries to prevent successful code execution from the TLS dissector heap overflow.
Requires vulnerability scanning to identify systems running affected Wireshark versions, enabling targeted remediation.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability is triggered when a user opens a specially crafted packet capture file containing malicious TLS traffic, directly enabling exploitation via T1204.002 Malicious File under User Execution, leading to possible code execution.
NVD Description
TLS protocol dissector heap overflow in Wireshark 4.6.0 to 4.6.4 allows denial of service and possible code execution
Deeper analysisAI
CVE-2026-5402 is a heap overflow vulnerability (CWE-122) in the TLS protocol dissector affecting Wireshark versions 4.6.0 through 4.6.4. Published on 2026-04-30, this flaw can lead to denial of service and possible code execution, earning a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).
Attackers can exploit this vulnerability remotely with low complexity and no required privileges, but it necessitates user interaction, such as convincing a Wireshark user to open a specially crafted packet capture file containing malicious TLS traffic. Successful exploitation grants high-impact access to confidentiality, integrity, and availability, potentially enabling arbitrary code execution on the affected system.
Wireshark security advisory WNPA-SEC-2026-14 (https://www.wireshark.org/security/wnpa-sec-2026-14.html) and the associated GitLab issue tracker (https://gitlab.com/wireshark/wireshark/-/issues/21090) provide details on mitigation, including patches and recommended actions for affected users.
Details
- CWE(s)