I received a similar warning in January 2013 and notified Execunet. They replied as follows:
We regularly schedule scans of our website and immediately address any vulnerability identified. We also have not received any reports from members or visitors to our website of malware or other malicious code on our site.
We take all reports of security issues seriously on our web site. Do you have a contact at Yandex that we can contact?
I look forward to hearing back from you.
Regards,
Kristen Mattera
Senior Member Services Representative
***** ext. 138
*****
www.execunet.com