skip to main content

Attention:

The NSF Public Access Repository (NSF-PAR) system and access will be unavailable from 11:00 PM ET on Thursday, May 23 until 2:00 AM ET on Friday, May 24 due to maintenance. We apologize for the inconvenience.


Title: Template Attack Against AES in Counter Mode With Unknown Initial Counter
Despite long-contested viability, numerous applications still rely upon Advance Encryption Standard (AES) in Counter mode (AES-CTR). Research supports that the vulnerabilities associated with CTR from a mathematical perspective, mainly forgery attempts, stem from misusing the nonce. When paired with cryptographic algorithms, assuming no nonce misuse increases the complexity of unraveling CTR. This paper examines the pairing of CTR with AES-128 (AES-CTR). It includes (1) full key recovery for a software implementation of AES-CTR utilizing a template attack (TA) and (2) enhancing the TA analysis's point of interest (POI) using first-order analysis and known key to identify leaky samples.  more » « less
Award ID(s):
1955231
NSF-PAR ID:
10429925
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
2023 IEEE 13th Annual Computing and Communication Workshop and Conference (CCWC)
Page Range / eLocation ID:
0525 to 0533
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. This paper provides efficient authenticated-encryption (AE) schemes in which a ciphertext is a commitment to the key. These are extended, at minimal additional cost, to schemes where the ciphertext is a commitment to all encryption inputs, meaning key, nonce, associated data and message. Our primary schemes are modifications of GCM (for basic, unique-nonce AE security) and AES-GCM-SIV (for misuse-resistant AE security) and add both forms of commitment without any increase in ciphertext size. We also give more generic, but somewhat more costly, solutions. 
    more » « less
  2. null (Ed.)
    We analyze the multi-user security of the streaming encryption in Google's Tink library via an extended version of the framework of nonce-based online authenticated encryption of Hoang et al. (CRYPTO'15) to support random-access decryption. We show that Tink's design choice of using random nonces and a nonce-based key-derivation function indeed improves the concrete security bound. We then give two better alternatives that are more robust against randomness failure. In addition, we show how to efficiently instantiate the key-derivation function via AES, instead of relying on HMAC-SHA256 like the current design in Tink. To accomplish this we give a multi-user analysis of the XOR-of-permutation construction of Bellare, Krovetz, and Rogaway (EUROCRYPT'98). 
    more » « less
  3. Data security plays a crucial role in all areas of data transmission, processing, and storage. This paper considers security in eavesdropping attacks over wireless communication links in aeronautical telemetry systems. Data streams in these systems are often encrypted by traditional encryption algorithms such as the Advanced Encryption Standard (AES). Here, we propose a secure coding technique for the integrated Network Enhanced Telemetry (iNET) communications system that can be coupled with modern encryption schemes. We consider a wiretap scenario where there are two telemetry links between a test article (TA) and a legitimate receiver, or ground station (GS). We show how these two links can be used to transmit both encrypted and unencrypted data streams while keeping both streams secure. A single eavesdropper is assumed who can tap into both links through its noisy channel. Since our scheme does not require encryption of the unencrypted data stream, the proposed scheme offers the ability to reduce the size of the required secret key while keeping the transmitted data secure. 
    more » « less
  4.  
    more » « less
  5. The customary formulation of authenticated encryption (AE) requires the decrypting party to supply the correct nonce with each ciphertext it decrypts. To enable this, the nonce is often sent in the clear alongside the ciphertext. But doing this can forfeit anonymity and degrade usability. Anonymity can also be lost by transmitting associated data (AD) or a session-ID (used to identify the operative key). To address these issues, we introduce anonymous AE, wherein ciphertexts must conceal their origin even when they are understood to encompass everything needed to decrypt (apart from the receiver’s secret state). We formalize a type of anonymous AE we call anAE, anonymous nonce-based AE, which generalizes and strengthens conventional nonce-based AE, nAE. We provide an efficient construction for anAE, NonceWrap, from an nAE scheme and a blockcipher. We prove NonceWrap secure. While anAE does not address privacy loss through traffic-flow analysis, it does ensure that ciphertexts, now more expansively construed, do not by themselves compromise privacy. 
    more » « less