Stellar Development Foundation released its Quantum Preparedness Plan, a phased roadmap to migrate the entire network to quantum-safe cryptography by the end of 2027. The plan addresses the threat posed by Shor's algorithm, which sufficiently advanced quantum computers could use to crack elliptic curve cryptography that Stellar and most blockchains currently rely on. The foundation identified dormant accounts as a significant challenge and will seek community input on recovery mechanisms, as quantum computing poses an industry-wide risk with the US National Institute of Standards and Technology revising its risk window to 2029 or earlier.
Shor's Algorithm Threatens Elliptic Curve Cryptography
The urgency behind the plan traces back to Shor's algorithm, a mathematical process that sufficiently advanced quantum computers could use to crack elliptic curve cryptography. Scientists at INRIA reduced the number of logical qubits needed to break 256-bit elliptic curves, while NIST revised its risk window to 2029 or earlier. Google is targeting post-quantum readiness by that same year.
Stellar identified two core risks. The first involves validator signatures, where a breach could destabilize network consensus. The second involves account takeover, where a quantum machine could derive a private key directly from a public one. With thousands of dormant accounts on the network, addressing that second threat at scale presents a challenge without an easy answer.
Stellar's Account Architecture Enables Key Rotation
Most blockchains tie an address directly to a public key, which means going quantum-safe typically requires moving assets to an entirely new account. Stellar's account addresses are separate from the signing keys attached to them. Users can add or swap signers through an existing operation called set_options without touching their address, balance, or transaction history. According to the foundation, that structural design gives the network a smoother path than many of its peers.
Three-Phase Migration Timeline Through 2027
The rollout is structured in three stages. Starting in 2026, post-quantum signature verification using NIST-standard algorithms ML-DSA-44 and ML-DSA-65 will be added to Soroban smart contracts, allowing enterprise wallets to begin migrating.
In 2027, a Core Advancement Proposal will bring quantum-safe signer types to classic accounts natively, letting all existing users add them alongside current keys.
The third stage—deprecation of the old Ed25519 standard—has no fixed date and will depend on how quantum computing develops and how ready the broader ecosystem is.
Zero-Knowledge Proof Systems Require Further Research
Zero-knowledge proof systems running on the network use pairing-based curves that are also vulnerable to quantum attack. The foundation acknowledged that this area still requires further research. Separate collaboration with ZK protocol teams is planned to address it.
FAQ
What is Stellar's Quantum Preparedness Plan timeline?
Stellar Development Foundation plans to migrate the entire network to quantum-safe cryptography by the end of 2027 through a three-phase rollout. The first phase begins in 2026 with post-quantum signature verification in Soroban smart contracts, followed by quantum-safe signer types for classic accounts in 2027.
Why are dormant accounts a challenge for Stellar's quantum migration?
Dormant accounts present a challenge because quantum computers could derive private keys from public keys to take over accounts. The foundation identified thousands of dormant accounts on the network and will seek community input on recovery mechanisms for inactive accounts.
