CORTEXA
← Browse
arxivcs.SDcs.AIcs.CR2026-07-18

Do Speech Tokens Leak Voiceprints? Speaker Inversion Attacks Against End-to-End Speech Language Models

Ye Lu, Yihan Yan, Zhaoyang Zhang, Zhitao Ou, Runze Liu, Li Liu, Shen Wang

End-to-end speech language models increasingly represent user speech with speech tokens rather than relying exclusively on cascaded ASR--LLM--TTS pipelines. Although these tokens support expressive and low-latency spoken interaction, they may also preserve sensitive speaker characteristics. We investigate whether exposed speech tokens leak voiceprints and formulate this risk as a speaker inversion attack. We introduce Audio BERT (AuB), a trainable model that constructs token embeddings from discrete codebooks and aggregates them into speaker-sensitive representations, and propose SpInv, a two-stage inversion method built on AuB to recover embeddings in the space of an attacker-specified speaker encoder. We evaluate Moshi, Higgs3, Kimi-Audio, and Qwen3-Omni using speaker-disjoint protocols on the VoxCeleb dataset. Extensive experiments show that, with only three seconds of frontend output, SpInv achieves cosine similarities above 0.70 in the attacker-specified speaker-encoder space.

View free PDFSource page

Related papers

arxiveess.AScs.AIcs.LGcs.SD2026-07-31

Stable Autoregressive Speech Generation with Low-Frame-Rate High-Dimensional Continuous Tokens

Yi Luo, Rongzhi Gu, Jixun Yao

Balancing sequence length, representational capacity, and long-horizon stability is a central problem in autoregressive (AR) speech and audio generation. Representations with higher frame rates or greater capacity can preserve more signal detail, but they also make streaming gene…

View free PDFSource page
arxivcs.CRcs.AI2026-07-31

MOSAIC: Masked Outsourcing of Secure AI Computations

James Hsin-yu Chiang, Sheila Zingg, Kari Kostiainen, Srdjan Capkun

We address the challenge of securely and efficiently outsourcing AI computations from a trusted but computationally weak client to an untrusted but powerful server, in the setting where the client holds both the input and the model, and the server must learn neither. We present M…

View free PDFSource page
arxivcs.CRcs.AI2026-07-23

Every Model Cheats: Prompt-Level Mitigation of Cheating on Offensive Cyber Tasks

Michael Kouremetis, Ads Dawson, Raja Sekhar Rao Dheekonda, Brian Greunke

Large language model (LLM) agents routinely cheat on cybersecurity benchmarks, inflating reported pass rates far beyond genuine capability. Prior audits of Cybench found cheating in 0.3-3.4% of traces, implicating only a handful of models. We present a controlled prompt-ablation…

View free PDFSource page
arxivcs.CRcs.AI2026-07-31

Memory Provenance Laundering in LLM Agents: A Non-Amplification Firewall for Persistent Memory

Jinghan Xu, Yiyong Xiao, Wanru Shao, Hankai Liu, Xinjin Li

Long-term memory lets large language model(LLM) agents reuse prior preferences and work flows, but it also turns untrusted observations into persistent action context. We identify memory provenance laundering: during LLM-based memory consolidation, an external observation may be…

View free PDFSource page