A denial-of-service vulnerability exists in Sysax Multi-Server version 6.10 via its SSH daemon. A specially crafted SSH key exchange packet can trigger a crash in the service, resulting in loss of availability. The flaw is triggered during the handling of malformed key exchange data, including a non-standard byte (x28) in place of the expected SSH protocol delimiter.
Weakness
An exception is thrown from a function, but it is not caught.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Multi_server | Sysax | 6.10 (including) | 6.10 (including) |
References
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/auxiliary/dos/windows/ssh/sysax_sshd_kexchange.rb
- https://www.mattandreko.com/2013/04/08/sysax-multi-server-6.10-ssh-dos/
- https://www.sysax.com/
- https://www.vulncheck.com/advisories/sysax-multi-server-sshd-key-exchange-dos
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/auxiliary/dos/windows/ssh/sysax_sshd_kexchange.rb
- https://www.mattandreko.com/2013/04/08/sysax-multi-server-6.10-ssh-dos/