Who Moved My Transaction? Uncovering Post-Transaction Auditability Vulnerabilities in Modern Super Apps
Junlin Liu, Zhaomeng Deng, Ziming Wang, Mengyu Yao, Yifeng Cai, Yutao Hu, Ziqi Zhang, Yao Guo, Ding Li
TL;DR
The paper investigates post-transaction auditability vulnerabilities in modern super apps, showing that pre-transaction defenses are insufficient if audit trails can be erased. It formalizes Post-Transaction Auditability and presents a threat model with opportunistic insiders and malicious software. An empirical study across six dominant super apps with six volunteers finds that approximately $83\%$ allow deletion of transaction records without strong authentication, with AliPay as the only app enforcing biometric verification. The work advocates a paradigm shift toward audit-trail integrity and proposes an automated benchmarking framework for broader, scalable assessment.
Abstract
Super apps are the cornerstones of modern digital life, embedding financial transactions into nearly every aspect of daily routine. The prevailing security paradigm for these platforms is overwhelmingly focused on pre-transaction authentication, preventing unauthorized payments before they occur. We argue that a critical vulnerability vector has been largely overlooked: the fragility of post-transaction audit trails. We investigate the ease with which a user can permanently erase their transaction history from an app's interface, thereby concealing unauthorized or sensitive activities from the account owner. To quantify this threat, we conducted an empirical study with 6 volunteers who performed a cross-evaluation on six super apps. Our findings are alarming: all six applications studied allow users to delete transaction records, yet a staggering five out of six (83+\%) fail to protect these records with strong authentication. Only one app in our study required biometric verification for deletion. This study provides the first concrete evidence of this near-ubiquitous vulnerability, demonstrating a critical gap in the current mobile security landscape and underscoring the urgent need for a paradigm shift towards ensuring post-transaction audit integrity.