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Martin Vechev

90 accepted papers

2026

Adaptive Generation of Bias-Eliciting Questions for LLMs

ICML 2026poster

Large language models (LLMs) are now widely deployed in user-facing applications, reaching hundreds of millions of users worldwide. Despite their widespread adoption, growing reliance on their outputs raises significant concerns, particularly as users may be exposed to model-inherent biases that dis…

Cited by 0SourceScholar
2026

AutoBaxBuilder: Bootstrapping Code Security Benchmarking

ICML 2026poster

As large language models (LLMs) see wide adoption in software engineering, the reliable assessment of the correctness and security of LLM-generated code is crucial. Notably, prior work showed that LLMs are prone to generating code with security vulnerabilities, highlighting that security is often ov…

Cited by 0SourceScholar
2026

CodeTaste: Can LLMs Generate Human-Level Code Refactorings?

ICML 2026poster

Large language model (LLM)-based coding agents can generate working code, but their solutions often introduce complexity, duplication, and architectural debt. Human developers address such issues through refactoring: behavior-preserving program transformations that improve structure and maintainabil…

Cited by 0SourceScholar
2026

Constrained Decoding of Diffusion LLMs with Context-Free Grammars

ICLR 2026poster

Large language models (LLMs) have shown promising performance across diverse domains. Many practical applications of LLMs, such as code completion and structured data extraction, require adherence to syntactic constraints specified by a formal language. Yet, due to their probabilistic nature, LLM ou…

Cited by 0SourcecodeScholar
2026

Fewer Weights, More Problems: A Practical Attack on LLM Pruning

ICLR 2026poster

Model pruning, i.e., removing a subset of model weights, has become a prominent approach to reducing the memory footprint of large language models (LLMs) during inference. Notably, popular inference engines, such as vLLM, enable users to conveniently prune downloaded models before they are deployed.…

Cited by 0SourcecodeScholar
2026

LLM Fingerprinting via Semantically Conditioned Watermarks

ICLR 2026oral

Most LLM fingerprinting methods teach the model to respond to a few fixed queries with predefined atypical responses (keys). This memorization often does not survive common deployment steps such as finetuning or quantization, and such keys can be easily detected and filtered from LLM responses, ulti…

Cited by 0SourcecodeScholar
2026

The Open Proof Corpus: A Large-Scale Study of LLM-Generated Mathematical Proofs

ICLR 2026poster

In recent months, large language models (LLMs) have made significant progress in mathematical proof generation, but further advancement is hindered by the lack of a large-scale, high-quality dataset of human-evaluated proofs. While expensive to create, such a dataset is essential for driving improve…

Cited by 0SourcecodeScholar
2026

Watch your steps: Dormant Adversarial Behaviors that Activate upon LLM Finetuning

ICLR 2026oral

Finetuning open-weight Large Language Models (LLMs) is standard practice for achieving task-specific performance improvements. Until now, finetuning has been regarded as a controlled and secure process in which training on benign datasets leads to predictable behaviors. In this paper, we demonstrate…

Cited by 0SourcecodeScholar
2025

Automated Benchmark Generation for Repository-Level Coding Tasks

ICML 2025poster

Code Agent development is an extremely active research area, where a reliable performance metric is critical for tracking progress and guiding new developments. This demand is underscored by the meteoric rise in popularity of SWE-Bench -- a benchmark that challenges code agents to generate patches a…

Cited by 1SourcePDFScholar
2025

Average Certified Radius is a Poor Metric for Randomized Smoothing

ICML 2025poster

Randomized smoothing (RS) is popular for providing certified robustness guarantees against adversarial attacks. The average certified radius (ACR) has emerged as a widely used metric for tracking progress in RS. However, in this work, for the first time we show that ACR is a poor metric for evaluati…

Cited by 1SourcePDFScholar
2025

BaxBench: Can LLMs Generate Correct and Secure Backends?

ICML 2025spotlight

Automatic program generation has long been a fundamental challenge in computer science. Recent benchmarks have shown that large language models (LLMs) can effectively generate code at the function level, make code edits, and solve algorithmic coding tasks. However, to achieve full automation, LLMs s…

Cited by 2SourcePDFScholar
2025

Black-Box Adversarial Attacks on LLM-Based Code Completion

ICML 2025poster

Modern code completion engines, powered by large language models (LLMs), assist millions of developers with their strong capabilities to generate functionally correct code. Due to this popularity, it is crucial to investigate the security implications of relying on LLM-based code completion. In this…

Cited by 1SourcePDFScholar
2025

Discovering Spoofing Attempts on Language Model Watermarks

ICML 2025poster

LLM watermarks stand out as a promising way to attribute ownership of LLM-generated text. One threat to watermark credibility comes from spoofing attacks, where an unauthorized third party forges the watermark, enabling it to falsely attribute arbitrary texts to a particular LLM. Despite recent work…

2025

GRAIN: Exact Graph Reconstruction from Gradients

ICLR 2025poster

Federated learning claims to enable collaborative model training among multiple clients with data privacy by transmitting gradient updates instead of the actual client data. However, recent studies have shown the client privacy is still at risk due to the, so called, gradient inversion attacks which…

2025

MathArena: Evaluating LLMs on Uncontaminated Math Competitions

NeurIPS 2025poster

The rapid advancement of reasoning capabilities in large language models (LLMs) has led to notable improvements on mathematical benchmarks. However, many of the most commonly used evaluation datasets (e.g., AIME 2024) are widely available online, making it difficult to disentangle genuine reasoning…

Cited by 0SourcecodeScholar
2025

MathConstruct: Challenging LLM Reasoning with Constructive Proofs

ICML 2025poster

While Large Language Models (LLMs) demonstrate impressive performance in mathematics, existing math benchmarks come with significant limitations. Many focus on problems with fixed ground-truth answers, and are often saturated due to problem simplicity or the viability of guessing or memorization. Cr…

Cited by 1SourcePDFScholar
2025

Mind the Gap: A Practical Attack on GGUF Quantization

ICML 2025poster

With the increasing size of frontier LLMs, post-training quantization has become the standard for memory-efficient deployment. Recent work has shown that basic rounding-based quantization schemes pose security risks, as they can be exploited to inject malicious behaviors into quantized models that r…

2025

MixAT: Combining Continuous and Discrete Adversarial Training for LLMs

NeurIPS 2025poster

Despite recent efforts in Large Language Model (LLM) safety and alignment, current adversarial attacks on frontier LLMs can still consistently force harmful generations. Although adversarial training has been widely studied and shown to significantly improve the robustness of traditional machine le…

Cited by 0SourcecodeScholar
2025

Polyrating: A Cost-Effective and Bias-Aware Rating System for LLM Evaluation

ICLR 2025poster

Rating-based human evaluation has become an essential tool to accurately evaluate the impressive performance of large language models (LLMs). However, current rating systems suffer from several important limitations: first, they fail to account for biases that significantly influence evaluation resu…

Cited by 0SourcePDFScholar
2025

Ward: Provable RAG Dataset Inference via LLM Watermarks

ICLR 2025poster

RAG enables LLMs to easily incorporate external data, raising concerns for data owners regarding unauthorized usage of their content. The challenge of detecting such unauthorized usage remains underexplored, with datasets and methods from adjacent fields being ill-suited for its study. We take sever…

Cited by 4SourcePDFScholar
2025

Watermarking Autoregressive Image Generation

NeurIPS 2025poster

Watermarking the outputs of generative models has emerged as a promising approach for tracking their provenance. Despite significant interest in autoregressive image generation models and their potential for misuse, no prior work has attempted to watermark their outputs at the token level. In this w…

Cited by 0SourcecodeScholar
2024

A Synthetic Dataset for Personal Attribute Inference

NeurIPS 2024poster

Recently powerful Large Language Models (LLMs) have become easily accessible to hundreds of millions of users world-wide. However, their strong capabilities and vast world knowledge do not come without associated privacy risks. In this work, we focus on the emerging privacy threat LLMs pose – the ab…

2024

Beyond Memorization: Violating Privacy via Inference with Large Language Models

ICLR 2024spotlight

Current privacy research on large language models (LLMs) primarily focuses on the issue of extracting memorized training data. At the same time, models’ inference capabilities have increased drastically. This raises the key question of whether current LLMs could violate individuals’ privacy by infer…

2024

ConStat: Performance-Based Contamination Detection in Large Language Models

NeurIPS 2024poster

Public benchmarks play an essential role in the evaluation of large language models. However, data contamination can lead to inflated performance, rendering them unreliable for model comparison. It is therefore crucial to detect contamination and estimate its impact on measured performance. Unfortu…

Cited by 7SourcePDFScholar
2024

Controlled Text Generation via Language Model Arithmetic

ICLR 2024spotlight

As Large Language Models (LLMs) are deployed more widely, customization with respect to vocabulary, style, and character becomes more important. In this work, we introduce model arithmetic, a novel inference framework for composing and biasing LLMs without the need for model (re)training or highly s…

2024

DAGER: Exact Gradient Inversion for Large Language Models

NeurIPS 2024poster

Federated learning works by aggregating locally computed gradients from multiple clients, thus enabling collaborative training without sharing private client data. However, prior work has shown that the data can actually be recovered by the server using so-called gradient inversion attacks. While th…

2024

Expressivity of ReLU-Networks under Convex Relaxations

ICLR 2024poster

Convex relaxations are a key component of training and certifying provably safe neural networks. However, despite substantial progress, a wide and poorly understood accuracy gap to standard networks remains, raising the question of whether this is due to fundamental limitations of convex relaxations…

Cited by 7SourcePDFScholar
2024

Guiding LLMs The Right Way: Fast, Non-Invasive Constrained Generation

ICML 2024poster

To ensure that text generated by large language models (LLMs) is in an expected format, constrained decoding methods propose to enforce strict formal language constraints during generation. However, as we show in this work, not only do such methods often incur performance overhead during generation,…

2024

Hiding in Plain Sight: Disguising Data Stealing Attacks in Federated Learning

ICLR 2024poster

Malicious server (MS) attacks have enabled the scaling of data stealing in federated learning to large batch sizes and secure aggregation, settings previously considered private. However, many concerns regarding the client-side detectability of MS attacks were raised, questioning their practicality.…

2024

Instruction Tuning for Secure Code Generation

ICML 2024poster

Modern language models (LMs) have gained widespread acceptance in everyday and professional contexts, particularly in programming. An essential procedure enabling this adoption is instruction tuning, which substantially enhances LMs' practical utility by training them to follow user instructions and…

2024

Mitigating Catastrophic Forgetting in Language Transfer via Model Merging

EMNLP 2024finding

As open-weight large language models (LLMs) achieve ever more impressive performance across a wide range of tasks in English, practitioners aim to adapt these models to different languages. However, such language adaptation is often accompanied by catastrophic forgetting of the base model’s capabili…

Cited by 9SourcePDFScholar
2024

Private Attribute Inference from Images with Vision-Language Models

NeurIPS 2024poster

As large language models (LLMs) become ubiquitous in our daily tasks and digital interactions, associated privacy risks are increasingly in focus. While LLM privacy research has primarily focused on the leakage of model training data, it has recently been shown that LLMs can make accurate privacy-in…

2024

Prompt Sketching for Large Language Models

ICML 2024poster

Many recent prompting strategies for large language models (LLMs) query the model multiple times sequentially -- first to produce intermediate results and then the final answer. However, using these methods, both decoder and model are unaware of potential follow-up prompts, leading to disconnected a…

2024

SPEAR: Exact Gradient Inversion of Batches in Federated Learning

NeurIPS 2024poster

Federated learning is a framework for collaborative machine learning where clients only share gradient updates and not their private data with a server. However, it was recently shown that gradient inversion attacks can reconstruct this data from the shared gradients. In the important honest-but-cur…

Cited by 6SourcePDFScholar
2024

SWT-Bench: Testing and Validating Real-World Bug-Fixes with Code Agents

NeurIPS 2024poster

Rigorous software testing is crucial for developing and maintaining high-quality code, making automated test generation a promising avenue for both improving software quality and boosting the effectiveness of code generation methods. However, while code generation with Large Language Models (LLMs) i…

2024

Self-contradictory Hallucinations of Large Language Models: Evaluation, Detection and Mitigation

ICLR 2024poster

Large language models (large LMs) are susceptible to producing text that contains hallucinated content. An important instance of this problem is self-contradiction, where the LM generates two contradictory sentences within the same context. In this work, we present a comprehensive investigation into…

2024

Understanding Certified Training with Interval Bound Propagation

ICLR 2024poster

As robustness verification methods are becoming more precise, training certifiably robust neural networks is becoming ever more relevant. To this end, certified training methods compute and then optimize an upper bound on the worst-case loss over a robustness specification. Curiously, training metho…

2023

Automated Classification of Model Errors on ImageNet

NeurIPS 2023poster

While the ImageNet dataset has been driving computer vision research over the past decade, significant label noise and ambiguity have made top-1 accuracy an insufficient measure of further progress. To address this, new label-sets and evaluation protocols have been proposed for ImageNet showing that…

2023

Certified Training: Small Boxes are All You Need

ICLR 2023top-25%

To obtain, deterministic guarantees of adversarial robustness, specialized training methods are used. We propose, SABR, a novel such certified training method, based on the key insight that propagating interval bounds for a small but carefully selected subset of the adversarial input region is suffi…

2023

Connecting Certified and Adversarial Training

NeurIPS 2023poster

Training certifiably robust neural networks remains a notoriously hard problem. While adversarial training optimizes under-approximations of the worst-case loss, which leads to insufficient regularization for certification, sound certified training methods, optimize loose over-approximations, leadin…

2023

Efficient Certified Training and Robustness Verification of Neural ODEs

ICLR 2023poster

Neural Ordinary Differential Equations (NODEs) are a novel neural architecture, built around initial value problems with learned dynamics which are solved during inference. Thought to be inherently more robust against adversarial perturbations, they were recently shown to be vulnerable to strong adv…

2023

FARE: Provably Fair Representation Learning with Practical Certificates

ICML 2023poster

Fair representation learning (FRL) is a popular class of methods aiming to produce fair classifiers via data preprocessing. Recent regulatory directives stress the need for FRL methods that provide practical certificates, i.e., provable upper bounds on the unfairness of any downstream classifier tra…

2023

Human-Guided Fair Classification for Natural Language Processing

ICLR 2023top-25%

Text classifiers have promising applications in high-stake tasks such as resume screening and content moderation. These classifiers must be fair and avoid discriminatory decisions by being invariant to perturbations of sensitive attributes such as gender or ethnicity. However, there is a gap between…

2023

Incentivizing Honesty among Competitors in Collaborative Learning and Optimization

NeurIPS 2023poster

Collaborative learning techniques have the potential to enable training machine learning models that are superior to models trained on a single entity’s data. However, in many cases, potential participants in such collaborative schemes are competitors on a downstream task, such as firms that each ai…

Cited by 14SourcePDFScholar
2023

TabLeak: Tabular Data Leakage in Federated Learning

ICML 2023poster

While federated learning (FL) promises to preserve privacy, recent works in the image and text domains have shown that training updates leak private client data. However, most high-stakes applications of FL (e.g., in healthcare and finance) use tabular data, where the risk of data leakage has not ye…

2022

(De-)Randomized Smoothing for Decision Stump Ensembles

NeurIPS 2022accept

Tree-based models are used in many high-stakes application domains such as finance and medicine, where robustness and interpretability are of utmost importance. Yet, methods for improving and certifying their robustness are severely under-explored, in contrast to those focusing on neural networks. Ta…

2022

Bayesian Framework for Gradient Leakage

ICLR 2022poster

Federated learning is an established method for training machine learning models without sharing training data. However, recent work has shown that it cannot guarantee data privacy as shared gradients can still leak sensitive information. To formalize the problem of gradient leakage, we propose a th…

2022

Boosting Randomized Smoothing with Variance Reduced Classifiers

ICLR 2022spotlight

Randomized Smoothing (RS) is a promising method for obtaining robustness certificates by evaluating a base model under noise. In this work, we: (i) theoretically motivate why ensembles are a particularly suitable choice as base models for RS, and (ii) empirically confirm this choice, obtaining state-o…

2022

Complete Verification via Multi-Neuron Relaxation Guided Branch-and-Bound

ICLR 2022poster

State-of-the-art neural network verifiers are fundamentally based on one of two paradigms: either encoding the whole verification problem via tight multi-neuron convex relaxations or applying a Branch-and-Bound (BaB) procedure leveraging imprecise but fast bounding methods on a large number of easie…

2022

LAMP: Extracting Text from Gradients with Language Model Priors

NeurIPS 2022accept

Recent work shows that sensitive user data can be reconstructed from gradient updates, breaking the key privacy promise of federated learning. While success was demonstrated primarily on image data, these methods do not directly transfer to other domains such as text. In this work, we propose LAMP,…

2022

Latent Space Smoothing for Individually Fair Representations

ECCV 2022poster

"Fair representation learning transforms user data into a representation that ensures fairness and utility regardless of the downstream application. However, learning individually fair representations, i.e., guaranteeing that similar individuals are treated similarly, remains challenging in high-dim…

2022

Learning to Configure Computer Networks with Neural Algorithmic Reasoning

NeurIPS 2022accept

We present a new method for scaling automatic configuration of computer networks. The key idea is to relax the computationally hard search problem of finding a configuration that satisfies a given specification into an approximate objective amenable to learning-based techniques. Based on this idea,…

Cited by 22SourcePDFScholar
2022

On Distribution Shift in Learning-based Bug Detectors

ICML 2022spotlight

Deep learning has recently achieved initial success in program analysis tasks such as bug detection. Lacking real bugs, most existing works construct training and test data by injecting synthetic bugs into correct programs. Despite achieving high test accuracy (e.g., >90%), the resulting bug detecto…

2021

Automated Discovery of Adaptive Attacks on Adversarial Defenses

NeurIPS 2021poster

Reliable evaluation of adversarial defenses is a challenging task, currently limited to an expert who manually crafts attacks that exploit the defense’s inner workings, or to approaches based on ensemble of fixed attacks, none of which may be effective for the specific defense at hand. Our key obser…

2021

Certify or Predict: Boosting Certified Robustness with Compositional Architectures

ICLR 2021poster

A core challenge with existing certified defense mechanisms is that while they improve certified robustness, they also tend to drastically decrease natural accuracy, making it difficult to use these methods in practice. In this work, we propose a new architecture which addresses this challenge and e…

Cited by 17SourcePDFScholar
2021

Efficient Certification of Spatial Robustness

AAAI 2021technical

Recent work has exposed the vulnerability of computer vision models to vector field attacks. Due to the widespread usage of such models in safety-critical applications, it is crucial to quantify their robustness against such spatial transformations. However, existing work only provides empirical rob…

2021

PODS: Policy Optimization via Differentiable Simulation

ICML 2021spotlight

Current reinforcement learning (RL) methods use simulation models as simple black-box oracles. In this paper, with the goal of improving the performance exhibited by RL algorithms, we explore a systematic way of leveraging the additional information provided by an emerging class of differentiable si…

Cited by 59SourcePDFScholar
2021

Robustness Certification for Point Cloud Models

ICCV 2021poster

The use of deep 3D point cloud models in safety-critical applications, such as autonomous driving, dictates the need to certify the robustness of these models to real-world transformations. This is technically challenging, as it requires a scalable verifier tailored to point cloud models that handle…

Cited by 33PDFcodeScholar
2021

Scalable Certified Segmentation via Randomized Smoothing

ICML 2021spotlight

We present a new certification method for image and point cloud segmentation based on randomized smoothing. The method leverages a novel scalable algorithm for prediction and certification that correctly accounts for multiple testing, necessary for ensuring statistical guarantees. The key to our app…

2021

TFix: Learning to Fix Coding Errors with a Text-to-Text Transformer

ICML 2021spotlight

The problem of fixing errors in programs has attracted substantial interest over the years. The key challenge for building an effective code fixing tool is to capture a wide range of errors and meanwhile maintain high accuracy. In this paper, we address this challenge and present a new learning-base…

2020

Adversarial Attacks on Probabilistic Autoregressive Forecasting Models

ICML 2020poster

We develop an effective generation of adversarial attacks on neural models that output a sequence of probability distributions rather than a sequence of single values. This setting includes the recently proposed deep probabilistic autoregressive forecasting models that estimate the probability distr…

2020

Certified Defense to Image Transformations via Randomized Smoothing

NeurIPS 2020poster

We extend randomized smoothing to cover parameterized transformations (e.g., rotations, translations) and certify robustness in the parameter space (e.g., rotation angle). This is particularly challenging as interpolation and rounding effects mean that image transformations do not compose, in turn p…

2020

Learning Certified Individually Fair Representations

NeurIPS 2020poster

Fair representation learning provides an effective way of enforcing fairness constraints without compromising utility for downstream users. A desirable family of such fairness constraints, each requiring similar treatment for similar individuals, is known as individual fairness. In this work, we int…

2019

Beyond the Single Neuron Convex Barrier for Neural Network Certification

NeurIPS 2019poster

We propose a new parametric framework, called k-ReLU, for computing precise and scalable convex relaxations used to certify neural networks. The key idea is to approximate the output of multiple ReLUs in a layer jointly instead of separately. This joint relaxation captures dependencies between the i…

2019

Boosting Robustness Certification of Neural Networks

ICLR 2019poster

We present a novel approach for the certification of neural networks against adversarial perturbations which combines scalable overapproximation methods with precise (mixed integer) linear programming. This results in significantly better precision than state-of-the-art verifiers on challenging feed…

Cited by 241SourcePDFScholar
2019

Certifying Geometric Robustness of Neural Networks

NeurIPS 2019poster

The use of neural networks in safety-critical computer vision systems calls for their robustness certification against natural geometric transformations (e.g., rotation, scaling). However, current certification methods target mostly norm-based pixel perturbations and cannot certify robustness agains…

2019

DL2: Training and Querying Neural Networks with Logic

ICML 2019oral

We present DL2, a system for training and querying neural networks with logical constraints. Using DL2, one can declaratively specify domain knowledge constraints to be enforced during training, as well as pose queries on the model to find inputs that satisfy a set of constraints. DL2 works by trans…

2018

Fast and Effective Robustness Certification

NeurIPS 2018poster

We present a new method and system, called DeepZ, for certifying neural network robustness based on abstract interpretation. Compared to state-of-the-art automated verifiers for neural networks, DeepZ: (i) handles ReLU, Tanh and Sigmoid activation functions, (ii) supports feedforward and convolution…

Cited by 674SourcePDFScholar
2018

Training Neural Machines with Trace-Based Supervision

ICML 2018oral

We investigate the effectiveness of trace-based supervision methods for training existing neural abstract machines. To define the class of neural machines amenable to trace-based supervision, we introduce the concept of a differential neural computational machine (dNCM) and show that several existin…