SSH: OpenSSH maxstartup Threshold Connection Exhaustion Denial of Service
This signature detects attempts to exploit a known vulnerability against OpenSSH server daemon (sshd). The vulnerability is due to a default configuration that only allows a small number of unauthenticated connections, after which the server will stop accepting any new connections. A remote unauthenticated attacker can exploit this vulnerability by creating a large number of connections to the SSH server, consuming all available connection slots. Repeated exploitation could result in a denial of service condition.
Extended Description
The default configuration of OpenSSH through 6.1 enforces a fixed time limit between establishing a TCP connection and completing a login, which makes it easier for remote attackers to cause a denial of service (connection-slot exhaustion) by periodically making many new TCP connections.
Affected Products
Openbsd openssh
References
CVE: CVE-2010-5107
Short Name
SSH:OPENSSH-MAXSTARTUP-DOS
Severity
Major
Recommended
False
Recommended Action
Drop
Category
SSH
Keywords
CVE-2010-5107 Connection Denial Exhaustion OpenSSH Service Threshold maxstartup of
Release Date
06/12/2015
Supported Platforms
srx-branch-12.3
srx-19.3
srx-branch-19.3
vsrx3bsd-19.2
srx-branch-19.4
vsrx-19.4
mx-12.3
mx-19.4
vmx-19.4
mx-19.3
vsrx3bsd-19.4
srx-19.4
vsrx-12.3
vmx-19.3
vsrx-19.2
srx-12.3
Sigpack Version
3761
False Positive
Unknown
Vendors
Openbsd
CVSS Score
5.0