Ettercap through version 0.8.4.1 contains an out‑of‑bounds read and size_t underflow flaw in the function that strips Strict‑Transport‑Security headers. The bug arises from a stale length value and an unchecked result of a memmem() call, allowing malicious data to corrupt memory. Because Ettercap typically runs with privileged rights, a successful exploitation could lead to arbitrary code execution on the host system.

The vulnerability affects Ettercap from the Ettercap project, specifically all releases up through 0.8.4.1. Users deploying any of these versions on systems where Ettercap operates as root are at risk.

The CVSS score of 7.2 indicates a high severity, and the EPSS score is not available, so the current public exploitation probability is unknown. The flaw is not listed in CISA’s KEV catalog. An attacker would need to control an HTTPS server whose traffic is captured by an Ettercap instance performing SSL interception. The vulnerability can be driven by a network‑based attack where the server sends crafted responses that trigger the out‑of‑bounds read, potentially leading to memory corruption and privilege escalation because Ettercap runs as root.