arXiv subjects

Zhonghao Liao

Publications and source records attributed to Zhonghao Liao.

2 recordsLinked to original sources

arXiv2026

Static Attribution of Android Residential Proxy Malware Using Graph Kernels

Android residential proxy applications represent a growing class of potentially-unwanted programs (PUPs) that covertly route third-party traffic through end-user devices, enabling ad fraud, credential abuse, and evasion of geolocation controls by sophisticated threat actors. Attributing an unknown APK to a specific proxy network remains challenging due to code reuse, SDK embedding, and obfuscation across proxy families. We present a static-analysis pipeline for automated proxyware family attribution, extracting graph-structured representations (control-flow and function-call graphs) and behavioral signatures from a labeled corpus of 3,365 Android proxy apps spanning four commercial proxy networks. We evaluate Weisfeiler-Lehman graph kernel features alone and fused with binary capability vectors across multiple classifiers. Using 5-fold DEX-grouped cross-validation to prevent data leakage, SGD achieves a macro F1 of 0.985 on the expanded dataset. To support explainability, we map classifier decisions to automatically generated Yara rules, achieving per-family accuracies up to 88.45\% after filtering non-discriminative signatures. Finally, we discuss these results in the context of the broader ecosystem. We find that from the expanded dataset, the majority of applications (51.4\%) still available through APKPure still contain embedded proxy SDK code. Further analysis of developer accounts reveals that 23 developers are responsible for other applications also containing such functionality, suggesting continuous and ongoing commercial relationships between proxy providers and developers.

cs.CR↗

arXiv2025

Practical, Generalizable and Robust Backdoor Attacks on Text-to-Image Diffusion Models

Text-to-image diffusion models (T2I DMs) have achieved remarkable success in generating high-quality and diverse images from text prompts, yet recent studies have revealed their vulnerability to backdoor attacks. Existing attack methods suffer from critical limitations: 1) they rely on unnatural adversarial prompts that lack human readability and require massive poisoned data; 2) their effectiveness is typically restricted to specific models, lacking generalizability; and 3) they can be mitigated by recent backdoor defenses. To overcome these challenges, we propose a novel backdoor attack framework that achieves three key properties: 1) \emph{Practicality}: Our attack requires only a few stealthy backdoor samples to generate arbitrary attacker-chosen target images, as well as ensuring high-quality image generation in benign scenarios. 2) \emph{Generalizability:} The attack is applicable across multiple T2I DMs without requiring model-specific redesign. 3) \emph{Robustness:} The attack remains effective against existing backdoor defenses and adaptive defenses. Our extensive experimental results on multiple T2I DMs demonstrate that with only 10 carefully crafted backdoored samples, our attack method achieves $>$90\% attack success rate with negligible degradation in benign image generation quality. We also conduct human evaluation to validate our attack effectiveness. Furthermore, recent backdoor detection and mitigation methods, as well as adaptive defense tailored to our attack are not sufficiently effective, highlighting the pressing need for more robust defense mechanisms against the proposed attack.

cs.CR↗