Assessing the Impact of Speaker Identity in Speech Spoofing Detection
Anh-Tuan Dao 1, Driss Matrouf 1, Nicholas Evans 2
Published on arXiv
2602.20805
Output Integrity Attack
OWASP ML Top 10 — ML09
Key Finding
The speaker-invariant MHFA-IVspk model reduces average equal error rate by 17.2% across four datasets compared to the baseline, with up to 48% EER reduction on the most challenging attack (A11).
SInMT (Speaker-Invariant Multi-Task)
Novel technique introduced
Spoofing detection systems are typically trained using diverse recordings from multiple speakers, often assuming that the resulting embeddings are independent of speaker identity. However, this assumption remains unverified. In this paper, we investigate the impact of speaker information on spoofing detection systems. We propose two approaches within our Speaker-Invariant Multi-Task framework, one that models speaker identity within the embeddings and another that removes it. SInMT integrates multi-task learning for joint speaker recognition and spoofing detection, incorporating a gradient reversal layer. Evaluated using four datasets, our speaker-invariant model reduces the average equal error rate by 17% compared to the baseline, with up to 48% reduction for the most challenging attacks (e.g., A11).
Key Contributions
- SInMT framework that unifies speaker-aware and speaker-invariant spoofing detection via a dual-head MHFA classifier with optional gradient reversal layer (GRL)
- Empirical demonstration that removing speaker identity information (via GRL) reduces average EER by 17.2% across four datasets and 48% for the hardest attack type (A11)
- Analysis of how explicit speaker identity modeling (speaker-aware) vs. suppression (speaker-invariant) each improve over the baseline MHFA spoofing detector
🛡️ Threat Analysis
The paper proposes and evaluates a detection system for spoofed/synthetic speech (audio deepfakes), which is AI-generated content detection — explicitly listed under ML09 output integrity. The SInMT framework improves the detector's ability to identify TTS and voice-conversion attacks.