---
OA_place: publisher
OA_type: gold
_id: '3211'
abstract:
- lang: eng
  text: We present an improved bound on the advantage of any q-query adversary at
    distinguishing between the CBC MAC over a random n-bit permutation and a random
    function outputting n bits. The result assumes that no message queried is a prefix
    of any other, as is the case when all messages to be MACed have the same length.
    We go on to give an improved analysis of the encrypted CBC MAC, where there is
    no restriction on queried messages. Letting m be the block length of the longest
    query, our bounds are about mq2/2n for the basic CBC MAC and mo(1)q2/2n for the
    encrypted CBC MAC, improving prior bounds of m2q2/2n. The new bounds translate
    into improved guarantees on the probability of forging these MACs.
acknowledgement: Pietrzak was supported by the Swiss National Science Foundation,
  project No. 200020-103847/1.
alternative_title:
- LNCS
article_processing_charge: No
author:
- first_name: Mihir
  full_name: Bellare, Mihir
  last_name: Bellare
- first_name: Krzysztof Z
  full_name: Pietrzak, Krzysztof Z
  id: 3E04A7AA-F248-11E8-B48F-1D18A9856A87
  last_name: Pietrzak
  orcid: 0000-0002-9139-1654
- first_name: Phillip
  full_name: Rogaway, Phillip
  last_name: Rogaway
citation:
  ama: 'Bellare M, Pietrzak KZ, Rogaway P. Improved security analyses for CBC MACs.
    In: <i>25th Annual International Cryptology Conference</i>. Vol 3621. Springer
    Nature; 2005:527-545. doi:<a href="https://doi.org/10.1007/11535218_32">10.1007/11535218_32</a>'
  apa: 'Bellare, M., Pietrzak, K. Z., &#38; Rogaway, P. (2005). Improved security
    analyses for CBC MACs. In <i>25th Annual International Cryptology Conference</i>
    (Vol. 3621, pp. 527–545). Santa Barbara, CA, United States: Springer Nature. <a
    href="https://doi.org/10.1007/11535218_32">https://doi.org/10.1007/11535218_32</a>'
  chicago: Bellare, Mihir, Krzysztof Z Pietrzak, and Phillip Rogaway. “Improved Security
    Analyses for CBC MACs.” In <i>25th Annual International Cryptology Conference</i>,
    3621:527–45. Springer Nature, 2005. <a href="https://doi.org/10.1007/11535218_32">https://doi.org/10.1007/11535218_32</a>.
  ieee: M. Bellare, K. Z. Pietrzak, and P. Rogaway, “Improved security analyses for
    CBC MACs,” in <i>25th Annual International Cryptology Conference</i>, Santa Barbara,
    CA, United States, 2005, vol. 3621, pp. 527–545.
  ista: 'Bellare M, Pietrzak KZ, Rogaway P. 2005. Improved security analyses for CBC
    MACs. 25th Annual International Cryptology Conference. CRYPTO: International Cryptology
    Conference, LNCS, vol. 3621, 527–545.'
  mla: Bellare, Mihir, et al. “Improved Security Analyses for CBC MACs.” <i>25th Annual
    International Cryptology Conference</i>, vol. 3621, Springer Nature, 2005, pp.
    527–45, doi:<a href="https://doi.org/10.1007/11535218_32">10.1007/11535218_32</a>.
  short: M. Bellare, K.Z. Pietrzak, P. Rogaway, in:, 25th Annual International Cryptology
    Conference, Springer Nature, 2005, pp. 527–545.
conference:
  end_date: 2005-08-18
  location: Santa Barbara, CA, United States
  name: 'CRYPTO: International Cryptology Conference'
  start_date: 2005-08-14
date_created: 2018-12-11T12:02:02Z
date_published: 2005-09-12T00:00:00Z
date_updated: 2026-07-02T07:55:53Z
day: '12'
doi: 10.1007/11535218_32
extern: '1'
fulldoi: https://doi.org/10.1007/11535218_32
intvolume: '      3621'
language:
- iso: eng
month: '09'
oa_version: None
page: 527 - 545
publication: 25th Annual International Cryptology Conference
publication_identifier:
  eisbn:
  - '9783540318705'
  isbn:
  - '9783540281146'
publication_status: published
publisher: Springer Nature
publist_id: '3469'
status: public
title: Improved security analyses for CBC MACs
type: conference
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 3621
year: '2005'
...