Ramsha Anwar | Searcharxiv

arXiv2026

Pick Two: An Adversarial Animal Survival Game

The "Pick Two" animal selection puzzle is a popular thought experiment in which two animal species must defend a human against the remaining animal attackers. While typically discussed informally, the scenario presents a heterogeneous coalition-selection problem involving complex interactions among agents with different capabilities and behaviors. In this work, we formalize Pick Two as an adversarial multi-agent optimization problem and develop a biologically inspired agent-based simulation framework to evaluate defender coalition effectiveness. Coalition performance is evaluated through 18,000 Monte Carlo simulations conducted in a Unity-based environment. Results show that coalition effectiveness is not additive and is instead dominated by interaction effects and scaling behavior. Overall, this study demonstrates how agent-based simulation can be used to analyze coalition effectiveness in adversarial environments and highlights the importance of emergent group dynamics in determining collective success.

cs.GT↗

arXiv2025

SpyChain: Multi-Vector Supply Chain Attacks on Small Satellite Systems

Small satellites are integral to scientific, commercial, and defense missions, but reliance on commercial off-the-shelf (COTS) hardware broadens their attack surface. Although supply chain threats are well studied in other cyber-physical domains, their feasibility and stealth in space systems remain largely unexplored. Prior work has focused on flight software, which benefits from strict security practices and oversight. In contrast, auxiliary COTS components often lack robust assurance yet enjoy comparable access to critical on-board resources, including telemetry, system calls, and the software bus. Despite this privileged access, the insider threat within COTS hardware supply chains has received little attention. In this work, we present SpyChain, the first end-to-end design and implementation of independent and colluding hardware supply chain threats targeting small satellites. Using NASA's satellite simulation (NOS3), we demonstrate that SpyChain can evade testing, exfiltrate telemetry, disrupt operations, and launch Denial of Service (DoS) attacks through covert channels that bypass ground monitoring. Our study traces an escalation from a simple solo component to dynamic, coordinating malware, introducing a taxonomy of stealth across five scenarios. We showcase how implicit trust in auxiliary components enables covert persistence and reveal novel attack vectors, highlighting a new multi-component execution technique that is now incorporated into the SPARTA matrix. Our findings are reinforced by acknowledgment and affirmation from NASA's NOS3 team. Finally, we implement lightweight onboard defenses, including runtime monitoring, to mitigate threats like SpyChain.

cs.CR↗