Breaking and fixing the HB+DB protocol - Archive ouverte HAL Access content directly
Conference Papers Year : 2017

Breaking and fixing the HB+DB protocol


The HB protocol and its HB + successor are lightweight authentication schemes based on the Learning Parity with Noise (LPN) problem. They both suffer from the so-called GRS-attack whereby a man-in-the-middle (MiM) adversary can recover the secret key. At WiSec 2015, Pagnin et al. proposed the HB+DB protocol: HB + with an additional distance-bounding dimension added to detect and counteract such MiM attacks. They showed experimentally that HB+DB was resistant to GRS adversaries, and also advanced HB+DB as a distance-bounding protocol, discussing its resistance to worst-case distance-bounding attackers. In this paper, we exhibit flaws both in the authentication and distance-bounding layers of HB+DB; these vulnerabilities encompass practical attacks as well as provable security shortcomings. First, we show that HB+DB may be impractical as a secure distance-bounding protocol, as its distance-fraud and mafia-fraud security-levels scale poorly compared to other distance-bounding protocols. Secondly, we describe an effective MiM attack against HB+DB: our attack refines the GRS-strategy and still leads to key-recovery by the attacker, yet this is not deterred by HB+DB's distance-bounding. Thirdly, we refute the claim that HB+DB's security against passive attackers relies on the hardness of the LPN problem. We also discuss how (erroneously) requiring such hardness, in fact, lowers HB+DB's efficiency and its resistance to authentication and distance-bounding attacks. Drawing on HB+DB's design flaws, we also propose a new distance-bounding protocol – BLOG. It retains parts of HB+DB, yet BLOG is provably secure, even – in particular – against MiM attacks. Moreover, BLOG enjoys better practical security (asymptotical in the security parameter).
Fichier principal
Vignette du fichier
WISEC17.pdf (482.97 Ko) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

hal-01588562 , version 1 (15-09-2017)



Ioana Boureanu, David Gerault, Pascal Lafourcade, Cristina Onete. Breaking and fixing the HB+DB protocol. ACM Conference on Security and Privacy in Wireless and Mobile Networks, Jul 2017, Boston, United States. pp.241 - 246, ⟨10.1145/3098243.3098263⟩. ⟨hal-01588562⟩
795 View
124 Download



Gmail Mastodon Facebook X LinkedIn More