Reaction Information Security

Penetration testing at its best.

Network penetration testing, web application security, firewall review, CHECK pen testing, server build review, social engineering..

Recommendations for Joseph Sheridan

"I have worked with Joe on several occasions and have found him to be one of the highest calibre consultants in his field. Joe has a thorough understanding of IT Security and I would recommend him to anyone." May 14, 2012

Top qualities: Great Results, Expert, High Integrity

James Spencer, Network Administrator at Irish Bank Resolution Corporation (formerly Anglo Irish Bank)

"Joe is an expert in his field. He is one of the most knowledgeable penetration testers I have met and consistently delivers high quality work in a professional manner. With excellent communication skills and a personable approach, he is a pleasure to work with. I have no hesitation in recommending Joe." September 13, 2011

Top qualities: Expert, Good Value, High Integrity

Harj Singh, CLAS Consultant and Director at Aristi.

"Joe is without doubt the 'best of the best' in the world of pen testing. He is the 'Carlsberg' of testing - he reaches where other pen testers can't reach; and can explain his findings to all levels of the business with clarity and efficiency. A true gem and cannot recommend him highly enough...." August 3, 2011

Top qualities: Personable, Expert, High Integrity

Nick Prescot, Compliance Analyst at Firehost.

"I had the pleasure of working with Joe on a short tactical assignment with a Financial Services client to close some outstanding audit points. I found Joe to be both a clear and diplomatic communicator, showing both technical pragmatism but also great attention to detail when required, which are skills i value in the areas of Security Assessment. I look forward to working with Joe again in the future" July 11, 2010

James Walker CISSP C|EH CCSK, IT Security Consultant/Solutions Architect (Contract), Close Brothers Group PLC- London

"Joseph's detailed understanding of vulnerability analysis and pen testing allowed him to work within the constraint of short timescales for a mutual client. Joseph also has great client-facing skills too, and I look forward to working with him again." June 9, 2010

Philip Stewart, CISSP, Director & Information Security Consultant, Excelgate Consulting

"I had the opportunity of working with Joe in Glasgow on a CHECK ITHC a while ago and found him to be very experienced and knowledgeable consultant, a worthy addition to any testing team." June 9, 2010

Lloyd Bridges, CLAS Consultant, Manager at Price Waterhouse Coopers

"As part of our HMG Impact Level 3 security accreditation for hosting eSourcing services, we were happy to engage your services during May2009 (for our first accreditation) as well as February 2010 (for the annual renewal). In both occasions, you diligently carried out the Penetration Testing of the eSourcing system, both through internal access to our systems during on-site visits as well as externally over the internet afterwards.

As verified by our IT staff as well as HMG's Accreditors, you demonstrated in-depth knowledge of the security aspects of our project. The findings of your tests were useful as they identified potential security holes/risks and you also provided guidelines for the mitigation of these risks. Hence, we succeeded in attaining the required security level for hosting eSourcing services within our premises. In short, your services were valuable to us and we would be in favour of reengaging your services in the future."

Stefanos Christakis, Project Manager at European Dynamics

"Joseph was commissioned through Aristi to provide application penetration testing, Citrix Virtual Desktop breakout testing and DMZ level network testing. This was in relation to an IT solution being deployed to service a contract with the Department and Work & Pensions. The testing was part of assuring our delivery against the ISO27001 standard.

I was very happy with the quality of work undertaken - the work was done in a very timely manner against tight timescales. The report provided was very thorough and gave detailed analysis of any weaknesses identified and also how to resolve these to a satisfactory standard. The breadth and depth of testing was good and the DWP Security Team professionals commented on the excellent report that was provided.

Communication was excellent throughout the process and I would be happy to recommend his work to others."

Matt Brook | Head of Infrastructure| Pinnacle People Limited

Joseph Sheridan, joe sheridan,ethical hacker, penetration tester, CHECK team leader, CREST consultant, it security

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