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Cross-lingual SMS spam detection using GAN-based augmentation for imbalanced datasets
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  • Published: 03 February 2026

Cross-lingual SMS spam detection using GAN-based augmentation for imbalanced datasets

  • Adnane Filali1,
  • Mohammad Shorfuzzaman2,
  • El Arbi Abdellaoui Alaoui3,
  • Mostafa Merras1,
  • Mohammed Es-Sabry4,
  • Achraf Berrajaa5,
  • Roobaea Alroobaea6 &
  • …
  • Amr Yousef7 

Scientific Reports , Article number:  (2026) Cite this article

We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.

Subjects

  • Engineering
  • Mathematics and computing

Abstract

SMS spam detection remains a critical challenge in mobile communication security, particularly when addressing the inherent class imbalance present in real-world datasets, where spam messages constitute only 13–15% of total communications. This study presents a comprehensive framework integrating advanced word embeddings, deep learning architectures, and Generative Adversarial Networks (GANs) for synthetic data augmentation to enhance SMS spam classification performance. A systematic evaluation is conducted across six machine learning algorithms (Support Vector Machine (SVM), Logistic Regression (LR), K-Nearest Neighbors (KNN), Decision Tree (DT), Stochastic Gradient Descent (SGD), Random Forest (RF)) and two deep learning models (Long Short-Term Memory (LSTM), Bidirectional LSTM (Bi-LSTM)), combined with five embedding techniques (Term Frequency–Inverse Document Frequency (TF-IDF), Bag of Words (BoW), Word2Vec, GloVe, Bidirectional Encoder Representations from Transformers (BERT)), resulting in 120 experimental configurations tested both with and without data augmentation. A novel GAN-based approach is employed to generate synthetic word embeddings rather than raw text, preserving semantic coherence while addressing dataset imbalance more effectively than traditional oversampling methods (Synthetic Minority Over-sampling Technique (SMOTE), Adaptive Synthetic Sampling (ADASYN)). Experimental validation on both the monolingual UCI SMS Spam Collection and multilingual datasets demonstrates that the optimal BERT+Bi-LSTM+GAN configuration achieves exceptional performance, with F1-scores of 97.61% (monolingual) and 94.44% (multilingual), surpassing existing state-of-the-art approaches. The comprehensive evaluation framework, incorporating Matthews Correlation Coefficient (MCC) and Cohen’s Kappa (CK), provides robust assessment for imbalanced classification scenarios. Results reveal that contextual embeddings consistently outperform traditional frequency-based methods, with BERT achieving perfect precision of 100% in baseline configurations. The study establishes strategic deployment guidelines: BERT configurations for maximum accuracy scenarios, Word2Vec approaches for balanced performance–efficiency requirements, and traditional methods for resource-constrained environments. Cross-linguistic validation confirms the universality of the approach, demonstrating only a 3.25% performance degradation in multilingual contexts. This research advances both theoretical understanding of imbalanced text classification and practical implementation of robust SMS spam detection systems, providing a methodological foundation applicable to broader cybersecurity and natural language processing challenges.

Data availability

The datasets analyzed during the current study are publicly available: - UCI SMS Spam Collection dataset : https://archive.ics.uci.edu/dataset/228/sms+spam+collection - Multilingual SMS Spam dataset : https://www.kaggle.com/datasets/rajnathpatel/multilingual-spam-data

Abbreviations

Acc:

Accuracy

ADASYN:

Adaptive synthetic sampling approach for imbalanced learning

AUC:

Area under the receiver operating characteristic curve

BCE:

Binary cross-entropy loss

BERT:

Bidirectional encoder representations from transformers

Bi-LSTM:

Bidirectional long short-term memory network

BoW:

Bag of words

CBOW:

Continuous bag of words

CK:

Cohen’s kappa coefficient

DT:

Decision tree

F1:

F1-score

FPR:

False positive rate

GAN:

Generative adversarial network

GloVe:

Global vectors for word representation

KNN:

K-nearest neighbors

LSTM:

Long short-term memory network

LR:

Logistic regression

MCC:

Matthews correlation coefficient

OTP:

One-time password

RF:

Random forest

ROC:

Receiver operating characteristic curve

SD:

Standard deviation

SGD:

Stochastic gradient descent

SMS:

Short message service

SMOTE:

Synthetic minority over-sampling technique

TF-IDF:

Term frequency–inverse document frequency

TT:

Training time

TTUR:

Two time-scale update rule

WGAN:

Wasserstein GAN

Word2Vec:

Word-to-vector embedding model

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Acknowledgements

The authors extend their appreciation to Taif University, Saudi Arabia, for supporting this work through project number (TU-DSPP-2024-17).

Funding

This research was funded by Taif University, Taif, Saudi Arabia, project number (TU-DSPP-2024-17).

Author information

Authors and Affiliations

  1. IMACS Laboratory, VIASSC Team, High School of Technology, Moulay Ismail University of Meknes, Meknes, Morocco

    Adnane Filali & Mostafa Merras

  2. Department of Software Engineering, College of Engineering and Advanced Computing, Alfaisal University, 11533, Riyadh, Saudi Arabia

    Mohammad Shorfuzzaman

  3. M2IP Team, 2MI Laboratory, Department of Sciences, Moulay Ismail University of Meknes, Meknes, Morocco

    El Arbi Abdellaoui Alaoui

  4. ISISA Laboratory, Faculty of Sciences, Abdelmalek Essaadi University, Tetouan, Morocco

    Mohammed Es-Sabry

  5. Department of Computer Science, Faculty of Sciences, University Mohamed First, Oujda, Morocco

    Achraf Berrajaa

  6. Department of Computer Science, College of Computers and Information Technology, Taif University, P.O. Box 11099, 21944, Taif, Saudi Arabia

    Roobaea Alroobaea

  7. Electrical Engineering Department, University of Business and Technology, 23435, Jeddah, Saudi Arabia

    Amr Yousef

Authors
  1. Adnane Filali
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  2. Mohammad Shorfuzzaman
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Contributions

A.F: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Data curation, Writing - original draft, Visualization, Project administration. M.S: Methodology, Software, Validation, Writing - review & editing, Supervision. E. A: Conceptualization, Resources, Writing - review & editing, Supervision, Project administration, Writing - original draft. M.M: Software, Validation, Investigation, Data curation, Writing - original draft. M.E:Methodology, Formal analysis, Writing - review & editing. A. B: Software, Validation, Data curation, Writing - review & editing. R.A: Resources, Writing - review & editing. A.Y: Validation, Writing - review & editing, Supervision.

Corresponding authors

Correspondence to Adnane Filali or Amr Yousef.

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Filali, A., Shorfuzzaman, M., Abdellaoui Alaoui, E. et al. Cross-lingual SMS spam detection using GAN-based augmentation for imbalanced datasets. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37769-4

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  • Received: 17 October 2025

  • Accepted: 25 January 2026

  • Published: 03 February 2026

  • DOI: https://doi.org/10.1038/s41598-026-37769-4

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Keywords

  • SMS spam detection
  • Generative adversarial networks
  • Imbalanced classification
  • Deep learning
  • Data augmentation
  • Multilingual text classification
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