CVE-2026-5403 is a heap-based buffer overflow vulnerability in the SBC codec implementation of Wireshark versions 4.6.0 through 4.6.4 and 4.4.0 through 4.4.14. This vulnerability can be triggered to cause a denial of service via application crash and potentially enable code execution. The CVSS 3.1 base score is 7.8, indicating high severity with attack vector local, low attack complexity, no privileges required, user interaction required, unchanged scope, and high impact on confidentiality, integrity, and availability. The vulnerability is categorized under CWE-122 (Heap-based Buffer Overflow). There is no vendor advisory or patch information currently available.

Successful exploitation can lead to denial of service by crashing Wireshark and may allow an attacker to execute arbitrary code with the privileges of the user running Wireshark. This could compromise system confidentiality, integrity, and availability. However, no known exploits are reported in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should exercise caution when analyzing untrusted network traffic containing SBC codec data. Avoid opening suspicious capture files and consider running Wireshark with limited privileges to reduce potential impact.