I enjoy a wide interest in various topics related to cryptography and coding theory, mainly related to concrete applications. Current research topics include privacy preserving techniques (MPC/FHE, ZK-SNARKs/STARKs, DeFi, Blockchains), algorithms and computation, post-quantum security...

Academic article

• Grassi, Lorenzo; Khovratovich, Dmitry; Rønjom, Sondre et al. (2022). The Legendre Symbol and the Modulo-2 Operator in Symmetric Schemes over Fⁿ <inf>p</inf>: Preimage Attack on Full Grendel. (external link)
• Beierle, Christof; Felke, Patrick; Leander, Gregor et al. (2022). Decomposing Linear Layers. (external link)
• Bardeh, Navid Ghaedi; Rønjom, Sondre (2019). Practical attacks on reduced-round AES. (external link)
• Bardeh, Navid Ghaedi; Rønjom, Sondre (2019). The Exchange Attack: How to Distinguish Six Rounds of AES with 2^88.2 Chosen Plaintexts. (external link)
• Rønjom, Sondre (2017). Improving algebraic attacks on stream ciphers based on linear feedback shift register over \mathbb {F}_{2^k}. (external link)
• Grassi, Lorenzo; Rechberger, Christian; Rønjom, Sondre (2017). A new structural-differential property of 5-round AES. (external link)
• Rønjom, Sondre; Bardeh, Navid Ghaedi; Helleseth, Tor (2017). Yoyo tricks with AES. (external link)
• Gong, Guang; Rønjom, Sondre; Helleseth, Tor et al. (2011). Fast discrete Fourier spectra attacks on stream ciphers. (external link)
• Rønsom, Sondre; Raddum, Håvard (2008). On the Number of Linearly Independent Equations Generated by XL. (external link)
• Rønjom, Sondre; Helleseth, Tor (2007). A new attack on the filter generator. (external link)
• Rønjom, Sondre; Helleseth, Tor (2007). Attacking the filter generator over GF(2^m). (external link)
• Rønjom, Sondre; Helleseth, Tor (2007). The linear vector space spanned by the nonlinear filter generator. (external link)
• Rønjom, Sondre; Gong, Guang; Helleseth, Tor (2007). On attacks on filtering generators using linear subspace structures. (external link)
• Rønjom, Sondre; Gong, Guang; Helleseth, Tor (2007). A survey of recent attacks on the filter generator. (external link)

Lecture

• Andersen, Anders; Berre, Tor; Ellingsen, Pål et al. (2019). Informasjonssikkerhet i høyere utdanning. (external link)

Article in business/trade/industry journal

• Andersen, Anders; Berre, Tor; Ellingsen, Pål et al. (2019). Informasjonssikkerhet i høyere utdanning. (external link)

Academic lecture

• Rønjom, Sondre; Leander, Gregor; Minaud, Brice (2015). A Generic Approach to Invariant Subspace Attacks: Cryptanalysis of Robin, iSCREAM and Zorro. (external link)
• Rønjom, Sondre; Cid, Carlos (2010). Nonlinear Equivalence of Stream Ciphers. (external link)

Academic chapter/article/Conference paper

• Helleseth, Tor; Rønjom, Sondre (2011). Simplifying algebraic attacks with univariate analysis. (external link)
• Helleseth, Tor; Hojsik, Michal; Rønjom, Sondre (2009). Algebraic Attacks on Filter and Combiner Generator. (external link)

Doctoral dissertation

• Rønjom, Sondre (2009). Cryptanalysis of ciphers over finite cyclic groups. (external link)

See a complete overview of publications in Cristin.