A Lightweight Defense Mechanism against Next Generation of Phishing Emails using Distilled Attention-Augmented BiLSTM

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Eskandarian, Morteza, Rabbani, Mahdi, Kaniyamattam, Arun, Nejati, Fatemeh, Mirani, Mansur, Piya, Gunjan, Opushnyev, Igor, Ghorbani, Ali A., Dadkhah, Sajjad
Natura: Preprint
Pubblicazione: 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912927474253824
author Eskandarian, Morteza
Rabbani, Mahdi
Kaniyamattam, Arun
Nejati, Fatemeh
Mirani, Mansur
Piya, Gunjan
Opushnyev, Igor
Ghorbani, Ali A.
Dadkhah, Sajjad
author_facet Eskandarian, Morteza
Rabbani, Mahdi
Kaniyamattam, Arun
Nejati, Fatemeh
Mirani, Mansur
Piya, Gunjan
Opushnyev, Igor
Ghorbani, Ali A.
Dadkhah, Sajjad
contents The current generation of large language models produces sophisticated social-engineering content that bypasses standard text screening systems in business communication platforms. Our proposed solution for mail gateway and endpoint deception detection operates in a privacy-protective manner while handling the performance requirements of network and mobile security systems. The MobileBERT teacher receives fine-tuning before its transformation into a BiLSTM model with multi-head attention which maintains semantic discrimination only with 4.5 million parameters. The hybrid dataset contains human-written messages together with LLM-generated paraphrases that use masking techniques and personalization methods to enhance modern attack resistance. The evaluation system uses five testing protocols which include human-only and LLM-only tests and two cross-distribution transfer tests and a production-like mixed traffic test to assess performance in native environments and across different distribution types and combined traffic scenarios. The distilled model maintains a weighted-F1 score difference of 1-2.5 points compared to the mixture split results of strong transformer baselines including ModernBERT, DeBERTaV3-base, T5-base, DeepSeek-R1 Distill Qwen-1.5B and Phi-4 mini while achieving 80-95\% faster inference times and 95-99\% smaller model sizes. The system demonstrates excellent performance in terms of accuracy and latency while maintaining a compact size which enables real-time filtering without acceleration hardware and supports policy-based management. The paper examines system performance under high traffic conditions and security measures for privacy protection and implementation methods for operational deployment.
format Preprint
id arxiv_https___arxiv_org_abs_2602_22250
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A Lightweight Defense Mechanism against Next Generation of Phishing Emails using Distilled Attention-Augmented BiLSTM
Eskandarian, Morteza
Rabbani, Mahdi
Kaniyamattam, Arun
Nejati, Fatemeh
Mirani, Mansur
Piya, Gunjan
Opushnyev, Igor
Ghorbani, Ali A.
Dadkhah, Sajjad
Cryptography and Security
The current generation of large language models produces sophisticated social-engineering content that bypasses standard text screening systems in business communication platforms. Our proposed solution for mail gateway and endpoint deception detection operates in a privacy-protective manner while handling the performance requirements of network and mobile security systems. The MobileBERT teacher receives fine-tuning before its transformation into a BiLSTM model with multi-head attention which maintains semantic discrimination only with 4.5 million parameters. The hybrid dataset contains human-written messages together with LLM-generated paraphrases that use masking techniques and personalization methods to enhance modern attack resistance. The evaluation system uses five testing protocols which include human-only and LLM-only tests and two cross-distribution transfer tests and a production-like mixed traffic test to assess performance in native environments and across different distribution types and combined traffic scenarios. The distilled model maintains a weighted-F1 score difference of 1-2.5 points compared to the mixture split results of strong transformer baselines including ModernBERT, DeBERTaV3-base, T5-base, DeepSeek-R1 Distill Qwen-1.5B and Phi-4 mini while achieving 80-95\% faster inference times and 95-99\% smaller model sizes. The system demonstrates excellent performance in terms of accuracy and latency while maintaining a compact size which enables real-time filtering without acceleration hardware and supports policy-based management. The paper examines system performance under high traffic conditions and security measures for privacy protection and implementation methods for operational deployment.
title A Lightweight Defense Mechanism against Next Generation of Phishing Emails using Distilled Attention-Augmented BiLSTM
topic Cryptography and Security
url https://arxiv.org/abs/2602.22250