- Cosmos Labs released Ledger Security 2026.1 on October 8, 2026, bundling Cosmos SDK v0.55.0 and CometBFT v0.40.0.
- The headline feature is native ML-DSA, a lattice-based signature scheme standardized by NIST as FIPS 204.
- Validators can rotate to it one at a time, with no hard fork for the rotation itself.
- Whether any live chain has adopted it is not answered by the sources we opened.
Cosmos chains can now use ML-DSA for validator consensus keys and for user account keys. The concern behind the work is long-term. No quantum computer that can break today’s elliptic-curve signatures is publicly known. But keys used on a public ledger stay visible forever, so developers want a migration path ready before such a machine exists. Cosmos has now shipped the tooling.
What changed in SDK v0.55
The docs name the key type ml_dsa_65 (ML-DSA-65, NIST security category 3). It works for user account keys and validator consensus keys. Validator operator keys and node keys do not support it, and node keys stay ed25519.
Rotation is validator-led. An existing chain can move one validator at a time. The operator submits a MsgRotateConsPubKey message, and CometBFT applies the change two block heights later. The validator keeps its address, voting power, and accumulated fees. Each rotation burns a fee set by the chain’s key_rotation_fee parameter, and a validator can rotate once per unbonding period.
The docs say a chain reaches post-quantum security once validators holding two-thirds of voting power use ML-DSA consensus keys. Two-thirds is the same threshold CometBFT uses to finalize blocks.
“No hard fork” applies to the key rotation only. A chain still has to upgrade its software to SDK 0.55 and CometBFT 0.40 first, and the docs note the two upgrade together, so the validator set has to coordinate that step. The chain must also allow ML-DSA in its consensus parameters before any validator rotates.
The size penalty
Post-quantum signatures are bulky. The Cosmos docs give these figures, and the per-block row is the docs’ own estimate, not a measurement from a live chain.
| Measure | ed25519 | ml_dsa_65 | Source |
|---|---|---|---|
| Public key size | 32 bytes | 1,952 bytes | Cosmos docs |
| Signature size | 64 bytes | about 3,309 bytes | Cosmos docs |
| Signature data per block (100 validators, 6 s blocks) | about 6 KB | about 331 KB | Cosmos docs estimate |
The same example works out to about 1.8 TB per year versus about 56 GB.
Why It Matters to You
If you hold ATOM or another token on a Cosmos chain, nothing changes for you today. Existing accounts keep working. The release gives chains a way to protect keys against a future quantum computer, and you’d feel it first if your chain upgrades and you choose to open a new ML-DSA account and move funds into it. Check your wallet and chain for support first.
Limits and open questions
- User accounts do not migrate in place. A post-quantum account means a new account and a transfer of funds.
- IBC counterparties must upgrade first. Chains that connect through
07-tendermintlight clients need CometBFT v0.40 or later before any validator rotates to ML-DSA. Older clients fail once an ML-DSA validator joins. - EVM chains are only partly covered. Validators can use ML-DSA consensus keys, but user accounts there need
eth_secp256k1. The docs say post-quantum user accounts are expected later through Ethereum’s account abstraction work. - Adoption is unconfirmed. Neither the Cosmos docs nor the Crypto Economy report says which chains have activated ML-DSA on mainnet or how many validators have rotated.
- The “90 days” is about tooling, not quantum safety. Crypto Economy reports that Cosmos Labs will drop its older key management tool, TMKMS, from its bug bounty program at the start of Q1 2027. That gives active validators about a 90 day window to move to the new cosmos-kms tool. It is not a deadline to adopt ML-DSA.
Frequently Asked Questions
Is every Cosmos chain now quantum-resistant?
No. Each chain decides whether to upgrade and enable ML-DSA, and the docs say a chain is post-quantum secure only after validators with two-thirds of voting power rotate. Individual accounts are only as strong as their own key.
Do I need to move my ATOM or other tokens?
Not because of this release alone. If you want a post-quantum account, the docs say you create a new ML-DSA account and transfer funds to it.
Is a quantum attack on blockchains imminent?
The sources do not say so. This release is preparation. The Cosmos docs describe the upgrade path but make no claim about when a capable quantum computer will exist.
Sources
- Cosmos Docs: v0.55 release (accessed Oct 13, 2026)
- Cosmos Docs: Post quantum keys (accessed Oct 13, 2026)
- Crypto Economy: Cosmos Prepares for the Quantum Era With New Post-Quantum Ledger Upgrade (Oct 8, 2026)