This host is installed with Beckhoff TwinCAT and is prone to denial of service vulnerability.

Successful exploitation will allow attackers to cause denial of service condition Impact Level: Application

Vendor has released a patch to fix the issue, please contact the vendor at 'patch@beckhoff.com' for patch information. For updates refer to http://www.beckhoff.de/twincat/

The flaw is caused by an error in the 'TCATSysSrv.exe' when performing an invalid read access, which can be exploited by remote attacker by sending malformed packet to port 48899/UDP.

Beckhoff TwinCAT Version 2.11 build 1553,Other versions may also be affected.

• http://aluigi.altervista.org/adv/twincat_1-adv.txt
• http://packetstormsecurity.org/files/view/105088
• http://secunia.com/advisories/45981
• http://www.exploit-db.com/exploits/17835
• http://www.us-cert.gov/control_systems/pdf/ICS-ALERT-11-256-06.pdf

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Updated on 2015-03-25