SearcharxivSearch

arXiv subjects

Sahand Moslemi

Publications and source records attributed to Sahand Moslemi.

3 recordsLinked to original sources

Historian: Reducing Manual Validation in APR Benchmarking via Evidence-Based Assessment

Assessing the correctness of patches generated by Automated Program Repair (APR) is a major bottleneck. Manual validation is labor-intensive and limited: exact matching overlooks valid variants, while semantic inspection is subjective and hard to reproduce. Existing Automated Patch Correctness Assessment (APCA) often relies on opaque predictive models that treat each patch as novel, repeatedly re-assessing semantically redundant patches. Our analysis of a large corpus of tool-generated patches reveals a duality: about 39% of unique correct patches are syntactic clones, suggesting opportunities for automation, yet about 65% of bugs have multiple distinct correct fixes, making single-reference assessment insufficient. We present Historian, a framework that leverages Large Language Models to perform multi-reference comparisons against a knowledge base of historically validated patches, producing traceable, evidence-based verdicts while conservatively isolating novel cases as Unknown. In leave-one-tool-out evaluation, Historian achieves 95.0% coverage with 88.4% accuracy, reducing manual validation to 5% of patches. As an evidence-based pre-filter, enhancing the accuracy of standalone APCA tools by up to 21.8% and enabling a hybrid pipeline with 86.2% overall accuracy and 100% coverage. A longitudinal analysis of tool-generated patches (2020-2024) shows that redundancy in repair attempts is common, indicating that many patches repeatedly rediscover established ones and strengthening the sustainability of evidence-based APR assessment.

cs.SE

Explicit Vulnerability Generation with LLMs: An Investigation Beyond Adversarial Attacks

Large Language Models (LLMs) are increasingly used as code assistants, yet their behavior when explicitly asked to generate insecure code remains poorly understood. While prior research has focused on unintended vulnerabilities, this study examines a more direct threat: open-source LLMs generating vulnerable code when prompted. We propose a dual experimental design: (1) Dynamic Prompting, which systematically varies vulnerability type, user persona, and prompt phrasing across structured templates; and (2) Reverse Prompting, which derives natural-language prompts from real vulnerable code samples. We evaluate three open-source 7B-parameter models (Qwen2, Mistral, Gemma) using static analysis to assess both the presence and correctness of generated vulnerabilities. Our results show that all models frequently generate the requested vulnerabilities, though with significant performance differences. Gemma achieves the highest correctness for memory vulnerabilities under Dynamic Prompting (e.g., 98.6% for buffer overflows), while Qwen2 demonstrates the most balanced performance across all tasks. We find that professional personas (e.g., "DevOps Engineer") consistently elicit higher success rates than student personas, and that the effectiveness of direct versus indirect phrasing is inverted depending on the prompting strategy. Vulnerability reproduction accuracy follows a non-linear pattern with code complexity, peaking in a moderate range. Our findings expose how LLMs' reliance on pattern recall over semantic reasoning creates significant blind spots in their safety alignments, particularly for requests framed as plausible professional tasks.

cs.SE

LLMShot: Reducing snapshot testing maintenance via LLMs

Snapshot testing has emerged as a critical technique for UI validation in modern software development, yet it suffers from substantial maintenance overhead due to frequent UI changes causing test failures that require manual inspection to distinguish between genuine regressions and intentional design changes. This manual triage process becomes increasingly burdensome as applications evolve, creating a need for automated analysis solutions. This paper introduces LLMShot, a novel framework that leverages Vision-Language Models (VLMs) to automatically analyze snapshot test failures through semantic classification of UI changes. To evaluate LLMShot's effectiveness, we developed a comprehensive dataset using a feature-rich iOS application with configurable feature flags, creating realistic scenarios that produce authentic snapshot differences representative of real development workflows. Our evaluation using Gemma3 models demonstrates strong classification performance, with the 12B variant achieving over 84% recall in identifying failure root causes while the 4B model offers practical deployment advantages with acceptable performance for continuous integration environments. However, our exploration of selective ignore mechanisms revealed significant limitations in current prompting-based approaches for controllable visual reasoning. LLMShot represents the first automated approach to semantic snapshot test analysis, offering developers structured insights that can substantially reduce manual triage effort and advance toward more intelligent UI testing paradigms.

cs.SE