As quantum computing advances, Post-Quantum Cryptography (PQC) schemes are adopted to replace classical algorithms. Among them is the Stateless Hash-Based Digital Signature Algorithm (SLH-DSA) that was recently standardized by NIST and is favored for its conservative security basis. In this work, we present the first software-only universal forgery attack on SLH-DSA, leveraging Rowhammer-induced bit flips to corrupt the internal state and forge signatures. While prior work targeted embedded systems and required physical access, our attack is software-only, targeting commodity desktop and server hardware, significantly broadening the threat model. We demonstrate full end-to-end attacks against SLH-DSA in OpenSSL 3.5.1, achieving universal forgery for the SHAKE-128f (deterministic), SHA2-128s, and SHAKE-192f (randomized) parameter sets after one hour (deterministic) or eight hours (randomized) of hammering and post-processing ranging from minutes to an hour, and showing theoretical attack complexities for most parameter sets. Our post-processing is informed by a novel complexity analysis that, given a concrete set of faulty signatures, identifies the most promising computational path to pursue. To enable the attack, we introduce Swage, a modular and extensible framework for implementing end-to-end Rowhammer-based fault attacks. Swage abstracts and automates key components of practical Rowhammer attacks. Unlike prior tooling, Swage is untangled from the attacked code, making it reusable and suitable for frictionless analysis of different targets. Our findings highlight that even theoretically sound PQC schemes can fail under real-world conditions, underscoring the need for additional implementation hardening or hardware defenses against Rowhammer.

翻译：随着量子计算的发展，后量子密码学方案正逐步取代经典算法。其中，无状态基于哈希的数字签名算法（SLH-DSA）因其保守的安全性基础而受到青睐，并已于近期被NIST标准化。在本研究中，我们首次提出了针对SLH-DSA的纯软件通用伪造攻击，利用Rowhammer诱导的比特翻转破坏内部状态并伪造签名。先前的研究主要针对嵌入式系统且需要物理访问，而我们的攻击是纯软件的，针对商用桌面和服务器硬件，显著扩大了威胁模型的范围。我们在OpenSSL 3.5.1中演示了对SLH-DSA的完整端到端攻击，针对SHAKE-128f（确定性）、SHA2-128s和SHAKE-192f（随机化）参数集，分别经过一小时（确定性）或八小时（随机化）的“锤击”以及数分钟至一小时的后续处理后，实现了通用伪造，并对大多数参数集展示了理论攻击复杂度。我们的后处理基于一种新颖的复杂度分析，该分析在给定一组具体错误签名的情况下，识别出最有希望的计算路径。为实现该攻击，我们引入了Swage，一个模块化且可扩展的框架，用于实现基于Rowhammer的端到端故障攻击。Swage抽象并自动化了实际Rowhammer攻击的关键组件。与先前的工具不同，Swage与受攻击代码解耦，使其可重用并适用于对不同目标进行无摩擦分析。我们的研究结果表明，即使在理论上可靠的PQC方案也可能在现实条件下失效，这凸显了对额外实现加固或针对Rowhammer的硬件防御的需求。