Paper 2026/1222
UCX is All You Need: A Universal Transform for Committing Authenticated Encryption
, University of California, San Diego, University of California, San Diego, King Abdulaziz City for Science and Technology, University of Washington, HUMAINAbstract
Emerging attacks and applications have motivated the development of transforms that turn a given AE scheme into a committing AE (cAE) one. We give a new transform called UCX with the following attributes: It does not require the starting scheme to be tag based, works for schemes in the broad AE5 framework rather than the limited AE1 one, and preserves both UNAE (Unique Nonce AE) and MRAE (Misuse Resistant AE) security. No prior transform is ``universal'' in the sense of having the combination of all these properties. The use of UCX in place of prior, limited transforms reduces the risk of error and failure in the real world, where choices may be made by application developers and hidden in software libraries. The committing security of UCX is shown in the ideal-cipher model, and its AE5-security in the standard model. To design UCX, we introduce and build a new primitive, that we call a Tweakable Committing Concealer, and that may be of independent interest.
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- A minor revision of an IACR publication in CRYPTO 2026
- Keywords
- Authenticated encryptionCommitting security
- Contact author(s)
-
mbellare @ ucsd edu
riranjan @ ucsd edu
NAlyami @ mcit gov sa
alomair @ kacst edu sa - History
- 2026-06-10: revised
- 2026-06-10: received
- See all versions
- Short URL
- https://ia.cr/2026/1222
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2026/1222,
author = {Mihir Bellare and Rishabh Ranjan and Nujud Senan and Basel Alomair},
title = {{UCX} is All You Need: A Universal Transform for Committing Authenticated Encryption},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/1222},
year = {2026},
url = {https://eprint.iacr.org/2026/1222}
}
