Paper 2014/724
Protecting Encrypted Cookies from Compression Side-Channel Attacks
Janaka Alawatugoda, Douglas Stebila, and Colin Boyd
Abstract
Compression is desirable for network applications as it saves bandwidth; however, when data is compressed before being encrypted, the amount of compression leaks information about the amount of redundancy in the plaintext. This side channel has led to successful CRIME and BREACH attacks on web traffic protected by the Transport Layer Security (TLS) protocol. The general guidance in light of these attacks has been to disable compression, preserving confidentiality but sacrificing bandwidth. In this paper, we examine two techniques---heuristic separation of secrets and fixed-dictionary compression---for enabling compression while protecting high-value secrets, such as cookies, from attack. We model the security offered by these techniques and report on the amount of compressibility that they can achieve.
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. Major revision. Financial Cryptography 2015
- Keywords
- CRIME attackBREACH attackSide-channel attacksData compressionTLSSSL
- Contact author(s)
- janaka alawatugoda @ qut edu au
- History
- 2014-12-30: revised
- 2014-09-17: received
- See all versions
- Short URL
- https://ia.cr/2014/724
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2014/724,
author = {Janaka Alawatugoda and Douglas Stebila and Colin Boyd},
title = {Protecting Encrypted Cookies from Compression Side-Channel Attacks},
howpublished = {Cryptology {ePrint} Archive, Paper 2014/724},
year = {2014},
url = {https://eprint.iacr.org/2014/724}
}
