Sysax Multi Server versions prior to 5.55 contains a stack-based buffer overflow in its SSH service. When a remote attacker supplies an overly long username during authentication, the server copies the input to a fixed-size stack buffer without proper bounds checking. This allows remote code execution under the context of the service.
https://www.vulncheck.com/advisories/sysax-multi-server-ssh-username-buffer-overflow
https://www.exploit-db.com/exploits/18557
https://www.exploit-db.com/exploits/18535
https://advisories.checkpoint.com/defense/advisories/public/2012/cpai-23-sepc.html
Published: 2025-08-13
Updated: 2025-08-14
Base Score: 9
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 9.3
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: Critical
EPSS: 0.00701