Post-Quantum Cryptography and the Future of Secure Code Signing
Imagine a future where quantum computers can break the encryption that keeps our digital world secure. It may sound like science fiction, but experts warn that this capability could become real within the next decade. Such machines could forge digital signatures or decrypt sensitive data at speeds far beyond what classical computers can achieve. This emerging risk has accelerated global efforts to develop post-quantum cryptography (PQC)—new cryptographic methods built to withstand both classical and quantum attacks.
In this article, we’ll explore why PQC-based code signing is becoming essential for secure software delivery, how standards like CNSA 2.0 are shaping the transition, and what steps organizations should take now to prepare.
The Growing Threat of Quantum Computing
Today’s widely used cryptographic algorithms—such as RSA and elliptic-curve cryptography—are based on mathematical problems that are extremely difficult for conventional computers to solve. However, quantum computers could potentially solve these problems rapidly using algorithms like Shor’s, making existing encryption vulnerable.
While a fully capable “cryptographically relevant” quantum computer does not exist yet, many experts believe one could be developed in the coming years. Once that threshold is crossed, attackers could:
Forge digital signatures and impersonate trusted software publishers
Push malicious updates disguised as legitimate
Decrypt previously captured encrypted data
Undermine long-term confidentiality of sensitive information
This is why global security agencies are urging organizations to begin adopting quantum-resistant cryptography now—before “Q-day” arrives. Even today, adversaries could be harvesting encrypted data and storing it for future decryption once quantum capabilities become strong enough.
It’s also important to distinguish quantum cryptography (which uses quantum physics for secure communication) from post-quantum cryptography, which uses classical algorithms that are designed to resist quantum attacks and run on existing hardware.
What Is Post-Quantum Cryptography?
Post-quantum cryptography refers to encryption and digital signature algorithms that are considered secure against quantum computers. Instead of relying on the same mathematical foundations as RSA or ECC, PQC algorithms use alternative structures—such as lattice problems, error-correcting codes, or advanced hash-based techniques.
In 2016, the U.S. National Institute of Standards and Technology (NIST) began a multi-year global process to evaluate and standardize PQC algorithms. After several rigorous rounds of review, key standards were introduced in 2022 and finalized in 2024. These include:
- ML-KEM (CRYSTALS-Kyber): A secure way for two parties to establish shared keys, ideal for encrypting data during communication.
- ML-DSA (CRYSTALS-Dilithium): A fast, secure digital signature method meant to replace older signature schemes like RSA/ECDSA.
CNSA 2.0, a Clear Roadmap for a Quantum-Resistant Future
The NSA’s Commercial National Security Algorithm Suite 2.0 (CNSA 2.0), announced in 2022, offers explicit guidance for transitioning U.S. government systems—along with critical infrastructure and industry partners—to quantum-resistant algorithms.
A major update in CNSA 2.0 is the approval of quantum-safe code signing, including hash-based signature schemes like LMS and XMSS, which are already standardized and deployable today. These algorithms allow organizations to secure long-term firmware and software releases against future quantum threats.
CNSA 2.0 also emphasizes the importance of NIST’s newer algorithms—ML-KEM and ML-DSA—as they become widely supported across hardware and software ecosystems.
The recommended transition timeline is ambitious:
Immediate: Begin supporting approved PQC algorithms
By 2025: PQC becomes the default for software and firmware signing
By 2030: Phase out RSA and ECC for CNSA-eligible systems
By 2035: Complete migration to fully quantum-resistant architectures
The message is clear: organizations that rely on secure software distribution must begin preparing now.
Why Code Signing Matters in a Post-Quantum World
Code signing is a foundational component of software trust. Digital signatures verify the integrity and authenticity of applications, firmware, and updates. If classical signature algorithms are broken by quantum computing, attackers could impersonate legitimate vendors and distribute malicious updates.
Adopting quantum-safe code signing ensures software remains trustworthy—even in a future where quantum computers can break traditional signatures.
Primary candidates for PQC code signing include:
Hash-based signatures (LMS, XMSS): Already standardized, highly secure, but require careful key-use tracking since keys are stateful
Lattice-based signatures (ML-DSA): Expected to become the preferred long-term option due to unlimited signing capability and strong performance
Practical Steps to Transition
Organizations can begin preparing by taking the following steps:
1. Identify Vulnerable Systems
Create an inventory of where cryptography is used—software signing, firmware updates, communication protocols, authentication systems, and internal tools. Prioritize mission-critical assets.
2. Implement Crypto-Agility
Design systems that allow cryptographic algorithms to be replaced without major re-engineering. Adopt standards that support multiple algorithms or hybrid signatures.
3. Begin Testing Early
Pilot PQC algorithms in non-production environments. Test signing and verification using LMS, XMSS, or ML-DSA to identify performance considerations or compatibility issues.
4. Engage with Vendors
Work closely with security tool providers, HSM vendors, and PKI partners. Many are already introducing PQC-compatible features. Ensure that your suppliers align with your migration timeline.
5. Strengthen Key Management
Use hardware security modules (HSMs) or TPMs to protect keys. Hash-based schemes require strict key-state tracking, making secure key management even more important.
6. Use Hybrid Signatures During Transition
Combine classical and PQC signatures to maintain backward compatibility while strengthening security.
7. Stay Informed
Monitor evolving standards, compliance requirements, and industry guidance. Incorporate PQC planning into your overall security strategy.
Embracing the Future of Secure Software Delivery
Moving to post-quantum cryptography is a major step—but it’s part of a broader modernization effort. A secure software supply chain also requires adherence to CNSA 2.0 guidelines, alignment with CA/Browser Forum rules, and adoption of crypto-agile development practices.
With quantum threats on the horizon, starting early provides a clear advantage. Organizations that begin testing and implementing PQC now will navigate the transition more smoothly and strengthen long-term trust in their software supply chain.
If your organization is ready to begin—or accelerate—this transition, Garantir is here to help. With deep expertise in quantum-safe cryptography and enterprise-grade signing infrastructure, our GaraTrust platform enables secure, high-performance code signing that aligns with CNSA 2.0 and CA/B Forum requirements without disrupting existing workflows.
Download our e-book on PQC and CNSA 2.0–compliant code signing.
Or contact us at info@garantir.io to learn how we can support your secure software delivery strategy.
