Somindu Abeydeera - Cognitive Warfare: When Defenders Stop Updating Their Mental Model

Australia’s social media ban for under 16 has been one riddled with problems, affecting children and parents alike with the use of invasive measures to keep children out, that consistently spit false positives, yet simultaneously are trivially bypassed by the attackers, by the children. The juniors of our world are starting to become ever more present in the cyber world, with pirating software, evading bans and firewalls, starting to build up. In this era where cyber is riddled with seniority and authority biases, children aren’t given room. Psychologically, this exposes how biases and slow belief updating cause designers to underestimate adaptive behaviour, especially when it comes from groups, they do not expect to be capable adversaries. This talk will reframe cyber defence as "cognitive warfare", where attackers are exploiting psychological inertia, delayed belief updating, culturally reinforced assumptions and more. Drawing on established findings in cognitive and behavioural psychology such as Ocean's Big Five model and the Behavioural Inhibition System (BIS), this talk will frame both blue, and red teaming as practices with deep personal psychological roots which are affected by the neurodiversity and personality traits of any person. I will examine how rapidly evolving actors outperform defenders, not through sophistication, but through flexibility. How in many cases, the fastest adaptations aren’t driven by experience, but by the absence of institutional assumptions. Rather than focusing on tools or detection logic, based on my experience playing both physical and online team CTF challenges, along with considerable research of the fields of psychology and cyber, this session will explore why adaptive thinkers with minimal institutional grounding often recognise emerging threats faster than highly experienced teams, and why failure to update internal mental world models has become one of the most reliable attack surfaces in modern security operations.