CVE-2026-125406

Description

Ettercap through 0.8.4.1 contains a stack buffer underwrite vulnerability in the telnet dissector in src/dissectors/ec_telnet.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 products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://github.com/Ettercap/ettercap/security/advisories/GHSA-w5ch-7c4x-crcc ↗
• https://github.com/Ettercap/ettercap/commit/1d8badb713579419a29a494bb463a1af59707e98 ↗
• https://github.com/Ettercap/ettercap/pull/1330 ↗
• https://github.com/Ettercap/ettercap/blob/v0.8.4.1/src/dissectors/ec_telnet.c#L150-L159 ↗
• https://www.vulncheck.com/advisories/ettercap-through-0.8.4.1-stack-buffer-underwrite-via-telnet-dissector-backspace-handling ↗