This event is in collaboration with The Yorkshire Cyber Security Cluster.


Ben Sloan, Lead Engineer in the UK Civil Service, helping the government to build interesting things at scale.


5:30pm - Light refreshments
6:30pm - Talk starts
7:30pm - Event ends


Have you ever upgraded a nuget package, then later found out that it almost led to the breach of millions of records of customer data? I have, and I’d like to tell you about it... Welcome to ‘The domino effect’.

This is an experience report / postmortem detailing how updating one of the most popular and common nuget packages in the world (probably in use in almost every .net project everywhere - Newtonsoft.Json) sparked a somewhat unpredictable chain of events which ultimately led to a customer database of millions of customers at a major e-commerce retailer becoming public, which could have been a major incident impacting peoples’ lives.

A thorough forensic investigation followed, and fortunately we were able to prove no data had been stolen or lost but only just by the skin of our teeth. This was the near-miss of all near-misses.

This talk looks at the ‘domino effect’ that happened from updating the package to data being left on a public and unprotected instance for almost two weeks.

This event is in collaboration with The Yorkshire Cyber Security Cluster.

The Yorkshire Cyber Security Cluster is an initiative created as part of the UK Cyber Security Forum to help businesses and organisations across the region to collaborate and build a stronger standard of cyber security as part of a knowledge exchange collective. The Yorkshire Cyber Security Cluster brings together recognised cyber security experts, a selection of academic institutions, charities, local bodies and the police force who are all, working together towards reducing cybercrime within Yorkshire and the surrounding regions.

Our events are for adults aged 16 years and over.

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This event is brought to you by: BCS South Yorkshire branch

The Domino Effect - South Yorkshire Branch
Date and time
Thursday 17 November, 5:30pm - 7:30pm
Sheffield Hallam University
Cantor Building, Room 9130
153 Arundel Street
S1 2NU
This event is sold out