Compromising sensitive information through Padding Oracle and Known Plaintext attacks in Encrypt-then-TLS scenarios

Daniel Espinoza Figueroa

Paper 2023/1790

Compromising sensitive information through Padding Oracle and Known Plaintext attacks in Encrypt-then-TLS scenarios

Daniel Espinoza Figueroa, Universidad Técnica Federico Santa María

Abstract

Let's consider a scenario where the server encrypts data using AES-CBC without authentication and then sends only the encrypted ciphertext through TLS (without IV). Then, having a padding oracle, we managed to recover the initialization vector and the sensitive data, doing a cybersecurity audit for a Chilean company.

Metadata

Available format(s): PDF
Category: Attacks and cryptanalysis
Publication info: Preprint.
Keywords: AES-CBC Padding Oracle Known Plaintext
Contact author(s): daniel espinozaf @ sansano usm cl
History: 2023-11-24: approved; 2023-11-20: received; See all versions
Short URL: https://ia.cr/2023/1790
License: CC BY

BibTeX

@misc{cryptoeprint:2023/1790,
      author = {Daniel Espinoza Figueroa},
      title = {Compromising sensitive information through Padding Oracle and Known Plaintext attacks in Encrypt-then-{TLS} scenarios},
      howpublished = {Cryptology {ePrint} Archive, Paper 2023/1790},
      year = {2023},
      url = {https://eprint.iacr.org/2023/1790}
}