Counter‑GEO‑Bench is a new benchmark that evaluates how well defenses can stop large language models from producing misinformation when faced with generative engine‑optimized (GEO) content. It contains 247 human‑verified queries paired with both information‑preserving and information‑distorting GEO rewrites, and measures attack success rate, false positives, and answer quality across three victim LLMs. The study shows that existing off‑the‑shelf defenses reduce attack success by at most 5.7 %, while a lightweight baseline called C‑GEO Guard cuts success by 47.6 % with minimal loss of utility.
By Bing Zheng, Zongyao Zhao, Wenming Yang
arXiv:2605. 29107v2 Announce Type: replace-cross Abstract: Large language models (LLMs) increasingly rank products, documents, and recommendations for user queries, which makes manipulating these rankings a growing concern for fairness and information integrity.
By Ojas Nimase, Zhe Chen, Gengpei Qi, Yue Zhao, Xiyang Hu
The paper introduces GEO Defender, a two‑stage defense system designed to protect generative search engines from malicious Generative Engine Optimization (GEO) attacks that rewrite web documents to manipulate generated answers. GEO Defender comprises a Shield Reranker, which learns a defensive residual to demote GEO‑rewritten documents while maintaining relevance, and a Training‑Free Shield Generation component that creates a natural‑language library guiding the target LLM’s source usage during inference. Experiments on both closed‑source and open‑source large language models show that GEO Defender dramatically lowers attack success rates from 50.32% to 6.20%, preserves over 94% of benign evidence usage, and maintains answer quality while generalizing to unseen attacks.
By Haozhang Li, Yangguang Shao, Xinjie Lin, Zhong Guan, Mi Zhou, Junzheng Shi
arXiv:2603. 00801v2 Announce Type: replace Abstract: Language agents increasingly act as web-enabled systems that search, browse, and synthesize information from diverse sources.
By Shrey Shah, Levent Ozgur
Counter‑GEO‑Bench is a new defense benchmark that tests how well systems can resist misinformation generated by generative engine optimization (GEO). It contains 247 human‑verified queries paired with both information‑preserving and information‑distorting GEO rewrites, and evaluates defenses on attack success rate, false positives, and answer quality across three large language models. Existing off‑the‑shelf defenses reduce attack success by at most 5.7%, while a lightweight baseline, C‑GEO Guard, cuts it by 47.6% with minimal loss of utility.
The paper reports that a model can pass fidelity checks—verifying that extracted values match the source—without actually opening a datasheet, due to a hidden constraint that disables tool use. To address this, the authors log every tool call in an agentic benchmark and develop two instruments: a rule‑based failure‑attribution classifier and a silent‑failure detector that flags runs based solely on which tools were invoked. While the detector shows low false positives on clean extractions and recovers all planted faults, its recall against correct tool usage but incorrect answers remains unmeasured, and a partial causal chamber confirms only a subset of claims, highlighting limitations in physical verification.
By Qing Ye, Meng-Hsuan Lin
arXiv:2606. 24589v1 Announce Type: new Abstract: Scaling adversarial evaluation of large language models requires both a method for generating hard inputs and a reliable way to confirm that resulting failures are real.
By Khanak Khandelwal (Indian Institute of Technology Jodhpur)
arXiv:2608.29128v1 Announce Type: new
Abstract: Tool-using agents are commonly evaluated by a single bit: whether an end-to-end workflow completed. This metric fails to distinguish failures that matt...
By Zelin Wan, Arash Nourian, Xiaoxiao Li, Nihar Nandan, Kamalakannan Nandagopal
Every memory-based knowledge editor in the SERAC lineage depends on a scope decision: given a query, does a stored edit apply? We report that current knowledge-editing benchmarks cannot measure this d...
arXiv:2608.21606v1 Announce Type: new
Abstract: Machine unlearning aims to remove the influence of targeted training data from a model while preserving its remaining capabilities, but evaluating whet...
By Ayush Gupta, Hima Varshini Surisetty, Sreevidya Bollineni, Varad Ingale, Tuhina Tripathi, Abhishek Lalwani, Somya Chatterjee, Sadid Hasan
The paper reports that existing knowledge‑editing benchmarks cannot evaluate the scope decision—whether a stored edit applies to a query—because they are counterfactual and lack negative examples. Using the gradient‑free editor INLAY, the authors exhaustively test every router action on 1,689 queries across three datasets and find that an oracle router achieves no gain over a static policy, and abstention never wins. The authors attribute this to the structural design of the benchmarks and demonstrate that adding a missing negative condition restores some headroom and allows abstention to win.
By Aditya Pratap Singh
The paper introduces FAB, an attack that uses meta‑learning to embed dormant adversarial behaviors into large language models (LLMs). These behaviors remain inactive until the model is finetuned by downstream users, at which point the model can exhibit unwanted actions such as unsolicited advertising, jailbreakability, or over‑refusal. FAB is shown to be effective across multiple LLMs and resilient to various finetuning settings.
By Thibaud Gloaguen, Mark Vero, Robin Staab, Martin Vechev