UBUNTU-CVE-2026-125406: High severity ubuntu/ettercap vulnerability
Ettercap through 0.8.4.1 contains a stack buffer underwrite vulnerability in the telnet dissector in src/dissectors/ectelnet.c that decrements the output pointer on backspace without a lower bound check. Attackers can send a telnet stream with more backspaces than preceding characters to write below the stack buffer, corrupting the stack of the Ettercap process that normally runs as root.
Affected Software
Event History
Frequently Asked Questions
Who is exposed to this issue?
Systems running Ettercap through version 0.8.4.1 are exposed when they process attacker-controlled Telnet traffic. The affected Ettercap process normally runs as root, so successful exploitation can compromise that process with root-level impact.
What does an attacker need to exploit it?
An attacker needs to send a Telnet stream containing more backspace characters than preceding characters. No privileges or user interaction are required, and the attack vector is adjacent network.
How can I determine whether my system is affected?
Check whether Ettercap is installed and whether its version is 0.8.4.1 or earlier. Exposure also depends on whether the installation is processing Telnet traffic through the Telnet dissector.