{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T16:34:37Z","timestamp":1771432477388,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T00:00:00Z","timestamp":1771372800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cryptography"],"abstract":"<jats:p>In the context of digital certification systems, the demand for privacy-preserving authentication is increasingly vital, particularly for critical applications that involve sensitive personal data. Traditional digital signatures provide a robust means of implementing such systems. However, they raise significant privacy concerns due to their public verifiability, which allows verifiers to prove the authenticity of the received sensitive data to third parties. Universal designated verifier signature (UDVS) schemes address these privacy risks by offering non-transferability, ensuring that only the specified verifier can confirm the validity of the designated verifier signature (DVS). However, despite their advantages, existing UDVS models exhibit vulnerabilities that may allow tracking of the user\u2019s authentications among cooperating verifiers and enable third parties to be convinced of the authenticity of sensitive user data by retrieving DVSs from different, non-cooperating verifiers. This paper presents a strategy to achieve strong non-transferability, which effectively addresses these vulnerabilities, by being the first to extend the concept of randomizability to UDVS schemes and their security properties. Our findings demonstrate that a randomizable UDVS scheme can serve as a solid foundation for constructing strong non-transferable UDVS schemes. Finally, we propose an efficient, strong, non-transferable UDVS scheme as an instantiation of our strategy, utilizing state-of-the-art Type 3 pairings, significantly improving upon previous constructions.<\/jats:p>","DOI":"10.3390\/cryptography10010014","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T15:28:18Z","timestamp":1771428498000},"page":"14","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Strong Non-Transferability from Randomizable Universal Designated Verifier Signatures"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1416-4394","authenticated-orcid":false,"given":"Magdalena","family":"Bertram","sequence":"first","affiliation":[{"name":"Secure Systems Engineering, Fraunhofer AISEC, 14199 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2783-1013","authenticated-orcid":false,"given":"Benjamin","family":"Zengin","sequence":"additional","affiliation":[{"name":"Secure Systems Engineering, Fraunhofer AISEC, 14199 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8388-6059","authenticated-orcid":false,"given":"Nicolas","family":"Buchmann","sequence":"additional","affiliation":[{"name":"Secure Systems Engineering, Fraunhofer AISEC, 14199 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8577-1318","authenticated-orcid":false,"given":"Marian","family":"Margraf","sequence":"additional","affiliation":[{"name":"Secure Systems Engineering, Fraunhofer AISEC, 14199 Berlin, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,18]]},"reference":[{"key":"ref_1","unstructured":"(2025, September 17). eIDAS\u2014Regulation (EU) No 910\/2014. Available online: https:\/\/eur-lex.europa.eu\/eli\/reg\/2014\/910\/oj."},{"key":"ref_2","unstructured":"(2025, September 17). eIDAS 2.0\u2014Amendment of Regulation (EU) No 910\/2014. Available online: https:\/\/eur-lex.europa.eu\/legal-content\/EN\/TXT\/?uri=celex%3A52021PC0281."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"320","DOI":"10.56553\/popets-2025-0018","article-title":"Real-World Deniability in Messaging","volume":"2025","author":"Collins","year":"2025","journal-title":"Proc. Priv. Enhancing Technol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Hazay, C., and Stam, M. (2023). Deniable Authentication When Signing Keys Leak. Advances in Cryptology\u2014EUROCRYPT 2023, Springer.","DOI":"10.1007\/978-3-031-30620-4"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1211","DOI":"10.1016\/j.dcan.2023.01.021","article-title":"Privacy-preserving authentication scheme based on zero trust architecture","volume":"10","author":"Tang","year":"2024","journal-title":"Digit. Commun. Netw."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"37734","DOI":"10.1109\/JIOT.2025.3585405","article-title":"Bilinear Pairing-Free Universal Designated Verifier Signatures for Private Access in Zero Trust Network","volume":"12","author":"Wang","year":"2025","journal-title":"IEEE Internet Things J."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Tan, H., Wang, M., Shen, J., Vijayakumar, P., Moh, S., and Wu, Q.M.J. (2025). Blockchain-Assisted Conditional Anonymous Authentication and Adaptive Tree-Based Group Key Agreement for VANETs. IEEE Trans. Dependable Secur. Comput., 1\u201316.","DOI":"10.1109\/TDSC.2025.3628884"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"5535","DOI":"10.1109\/TVT.2020.2981934","article-title":"On the Design of Conditional Privacy Preserving Batch Verification-Based Authentication Scheme for Internet of Vehicles Deployment","volume":"69","author":"Sutrala","year":"2020","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1007\/978-3-540-40061-5_33","article-title":"Universal Designated-Verifier Signatures","volume":"Volume 2894","author":"Laih","year":"2003","journal-title":"Advances in Cryptology\u2014ASIACRYPT 2003"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1007\/s10207-007-0021-2","article-title":"Secure universal designated verifier signature without random oracles","volume":"7","author":"Huang","year":"2008","journal-title":"Int. J. Inf. Sec."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1007\/11496137_33","article-title":"Short Signature and Universal Designated Verifier Signature Without Random Oracles","volume":"Volume 3531","author":"Ioannidis","year":"2005","journal-title":"Applied Cryptography and Network Security\u2014ACNS 2005"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1007\/11832072_5","article-title":"Universal Designated Verifier Signatures Without Random Oracles or Non-black Box Assumptions","volume":"Volume 4116","author":"Prisco","year":"2006","journal-title":"Security and Cryptography for Networks\u2014SCN 2006"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1142\/S0129054109006474","article-title":"New Extensions of Pairing-Based Signatures into Universal (Multi) Designated Verifier Signatures","volume":"20","author":"Vergnaud","year":"2009","journal-title":"Int. J. Found. Comput. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1007\/s10207-011-0146-1","article-title":"Efficient strong designated verifier signature schemes without random oracle or with non-delegatability","volume":"10","author":"Huang","year":"2011","journal-title":"Int. J. Inf. Secur."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.ins.2018.12.020","article-title":"Universal designated verifier signature scheme with non-delegatability in the standard model","volume":"479","author":"Rastegari","year":"2019","journal-title":"Inf. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"817","DOI":"10.1007\/s10586-013-0255-x","article-title":"A systematic method to design strong designated verifier signature without random oracles","volume":"16","author":"Tian","year":"2013","journal-title":"Clust. Comput."},{"key":"ref_17","unstructured":"Asaar, M.R., and Salmasizadeh, M. (2025, September 17). A Pairing Based Strong Designated Verifier Signature Scheme Without Random Oracles. Cryptology ePrint Archive, Paper 2012\/061, 2012. Available online: https:\/\/eprint.iacr.org\/2012\/061."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1007\/978-3-319-29485-8_7","article-title":"Short Randomizable Signatures","volume":"Volume 9610","author":"Sako","year":"2016","journal-title":"Topics in Cryptology\u2014CT-RSA 2016"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1007\/978-3-319-76953-0_17","article-title":"Reassessing Security of Randomizable Signatures","volume":"Volume 10808","author":"Smart","year":"2018","journal-title":"Topics in Cryptology\u2014CT-RSA 2018"},{"key":"ref_20","unstructured":"Wu, J., and Stinson, D.R. (2025, September 17). An Efficient Identification Protocol and the Knowledge-of-Exponent Assumption. Cryptology ePrint Archive, Paper 2007\/479, 2007. Available online: https:\/\/eprint.iacr.org\/2007\/479."},{"key":"ref_21","first-page":"212","article-title":"Undeniable Signatures","volume":"Volume 435","author":"Brassard","year":"1989","journal-title":"Advances in Cryptology\u2014CRYPTO 1989"},{"key":"ref_22","first-page":"143","article-title":"Designated Verifier Proofs and Their Applications","volume":"Volume 1070","author":"Maurer","year":"1996","journal-title":"Advances in Cryptology\u2014EUROCRYPT 1996"},{"key":"ref_23","first-page":"105","article-title":"Designated Verifier Signatures: Anonymity and Efficient Construction from Any Bilinear Map","volume":"Volume 3352","author":"Laguillaumie","year":"2005","journal-title":"Security in Communication Networks; Lecture Notes in Computer Science"},{"key":"ref_24","first-page":"13","article-title":"Non-Delegatable Strong Designated Verifier Signature Using a Trusted Third Party without Pairings","volume":"Volume 138","author":"Thomborson","year":"2013","journal-title":"Proceedings of the AISC 2013"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1007\/11689522_20","article-title":"Short (Identity-Based) Strong Designated Verifier Signature Schemes","volume":"Volume 3903","author":"Chen","year":"2006","journal-title":"Information Security Practice and Experience\u2014ISPEC 2006"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1016\/j.compeleceng.2008.05.004","article-title":"Identity-based strong designated verifier signature schemes: Attacks and new construction","volume":"35","author":"Kang","year":"2009","journal-title":"Comput. Electr. Eng."},{"key":"ref_27","first-page":"495","article-title":"Multi-designated Verifiers Signatures","volume":"Volume 3269","author":"Qing","year":"2004","journal-title":"Information and Communications Security\u2014ICICS 2004"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/j.csi.2008.02.003","article-title":"Comment on Saeednia et al.\u2019s strong designated verifier signature scheme","volume":"31","author":"Lee","year":"2009","journal-title":"Comput. Stand. Interfaces"},{"key":"ref_29","first-page":"40","article-title":"An Efficient Strong Designated Verifier Signature Scheme","volume":"Volume 2971","author":"Lim","year":"2003","journal-title":"Information Security and Cryptology\u2014ICISC 2003"},{"key":"ref_30","first-page":"313","article-title":"Identity-Based Strong Designated Verifier Signature Schemes","volume":"Volume 3108","author":"Wang","year":"2004","journal-title":"Information Security and Privacy\u2014ACISP 2004"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"766","DOI":"10.1016\/j.ins.2007.07.005","article-title":"A novel ID-based designated verifier signature scheme","volume":"178","author":"Zhang","year":"2008","journal-title":"Inf. Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1007\/978-3-540-24632-9_7","article-title":"Efficient Extension of Standard Schnorr\/RSA Signatures into Universal Designated-Verifier Signatures","volume":"Volume 2947","author":"Bao","year":"2004","journal-title":"Public Key Cryptography\u2014PKC 2004"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"685","DOI":"10.1007\/s11859-008-0610-6","article-title":"Universal designated multi verifier signature scheme without random oracles","volume":"13","author":"Ming","year":"2008","journal-title":"Wuhan Univ. J. Nat. Sci."},{"key":"ref_34","first-page":"459","article-title":"Designated Verifier Signature Schemes: Attacks, New Security Notions and a New Construction","volume":"Volume 3580","author":"Caires","year":"2005","journal-title":"Automata, Languages and Programming\u2014ICALP 2005"},{"key":"ref_35","first-page":"479","article-title":"Universal Designated Verifier Signature Without Delegatability","volume":"Volume 4307","author":"Ning","year":"2006","journal-title":"Information and Communications Security\u2014ICICS 2006"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/j.ins.2014.05.020","article-title":"On delegatability of designated verifier signature schemes","volume":"281","author":"Shim","year":"2014","journal-title":"Inf. Sci."},{"key":"ref_37","first-page":"219","article-title":"Non-delegatable Strong Designated Verifier Signature on Elliptic Curves","volume":"Volume 7259","author":"Kim","year":"2011","journal-title":"Information Security and Cryptology\u2014ICISC 2011"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1289","DOI":"10.1016\/j.mcm.2013.01.010","article-title":"A non-delegatable strong designated verifier signature in ID-based setting for mobile environment","volume":"58","author":"Tian","year":"2013","journal-title":"Math. Comput. Model."},{"key":"ref_39","unstructured":"Xhafa, F., Barolli, L., Pop, F., Chen, X., and Cristea, V. (2012). A Non-delegatable Strong Designated Verifier Signature without Random Oracles. 2012 Fourth International Conference on Intelligent Networking and Collaborative Systems\u2014INCoS 2012, IEEE."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1007\/s11704-013-3120-4","article-title":"A short non-delegatable strong designated verifier signature","volume":"8","author":"Tian","year":"2014","journal-title":"Front. Comput. Sci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"3113","DOI":"10.1016\/j.dam.2007.12.010","article-title":"Pairings for cryptographers","volume":"156","author":"Galbraith","year":"2008","journal-title":"Discret. Appl. Math."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Mrabet, N.E., and Joye, M. (2017). Guide to Pairing-Based Cryptography, Chapman and Hall\/CRC.","DOI":"10.1201\/9781315370170"},{"key":"ref_43","first-page":"467","article-title":"Still wrong use of pairings in cryptography","volume":"333","author":"Uzunkol","year":"2018","journal-title":"Appl. Math. Comput."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1007\/s10207-013-0190-0","article-title":"Adaptive CCA broadcast encryption with constant-size secret keys and ciphertexts","volume":"12","author":"Phan","year":"2013","journal-title":"Int. J. Inf. Sec."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Yung, M., Dodis, Y., Kiayias, A., and Malkin, T. (2006). Strongly Unforgeable Signatures Based on Computational Diffie-Hellman. Public Key Cryptography\u2014PKC 2006, Springer.","DOI":"10.1007\/11745853"}],"container-title":["Cryptography"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2410-387X\/10\/1\/14\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T15:49:23Z","timestamp":1771429763000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2410-387X\/10\/1\/14"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,18]]},"references-count":45,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["cryptography10010014"],"URL":"https:\/\/doi.org\/10.3390\/cryptography10010014","relation":{},"ISSN":["2410-387X"],"issn-type":[{"value":"2410-387X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,18]]}}}