Parshyn, OleksandrKhmelnytskyi, Mykola2026-03-022026-03-022025Parshyn, O. Differential Attack on IDEA Block Cipher Based on Its Key-Adding Function / Oleksandr Parshyn, Mykola Khmelnytskyi // Theoretical and Applied Cybersecurity: scientific journal. – 2025. – Vol. 7, No. 3. – P. 38-44. – Bibliogr.: 14 ref.https://ela.kpi.ua/handle/123456789/79150This paper examines a new theoretical differential attack on the IDEA block cipher and several relatedciphers from the same design family, such as PES and MESH. We present an analysis of the mostprobable differentials, which characterise the ciphers’ security against the proposed attack. We alsopropose a design modification targeting the cipher’s key-adding function to enhance its security againstthe attackensymmetric cryptographyblock cipherLai-Massey schemeIDEAdifferential cryptanalysisArticleP. 38-44https://doi.org/10.20535/tacs.2664-29132025.3.345793004.056.55:512.6+519.688