---
title: "Is proof of stake secure?"
url: "https://worldwiki.io/q/is-proof-of-stake-secure"
type: "question"
language: "en"
intent: "informational"
entity: "Proof of Stake"
topic: "Blockchain"
published: "2026-09-18 07:10:23"
updated: "2026-09-18 16:10:23"
---

# Is proof of stake secure?

## Short answer

Proof of stake can be secure, but its security depends on how the stake is spread among validators. On Ethereum, an attacker with 33% of the stake could stop blocks from being finalized. With more than 50%, it could censor transactions. With 66% or more, it could finalize its own version of history. Ethereum's defences include slashing, the inactivity leak, weak subjectivity checkpoints against long-range attacks, and community coordination to recover from an attack.

## Answer

Known weaknesses discussed in the literature include the nothing-at-stake problem and long-range attacks [4][5]. Critics also point to stake becoming concentrated through liquid staking providers [2][5].

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## Sources

1. [Proof-of-stake (PoS)](https://ethereum.org/developers/docs/consensus-mechanisms/pos/) — ethereum.org · evidence page: https://worldwiki.io/source/161
2. [Proof-of-stake vs proof-of-work](https://ethereum.org/developers/docs/consensus-mechanisms/pos/pos-vs-pow/) — ethereum.org · evidence page: https://worldwiki.io/source/208
3. [The Merge](https://ethereum.org/roadmap/merge/) — ethereum.org · evidence page: https://worldwiki.io/source/160
4. [Ethereum proof-of-stake attack and defense](https://ethereum.org/developers/docs/consensus-mechanisms/pos/attack-and-defense/) — ethereum.org · evidence page: https://worldwiki.io/source/209
5. [Proof-of-stake Frequently Asked Questions](https://ethereum.org/developers/docs/consensus-mechanisms/pos/faqs) — ethereum.org · evidence page: https://worldwiki.io/source/210
6. [Prague-Electra (Pectra)](https://ethereum.org/roadmap/pectra/) — ethereum.org · evidence page: https://worldwiki.io/source/201
7. [Ethereum Activates 'Pectra' Upgrade, Raising Max Stake to 2,048 ETH](https://www.coindesk.com/tech/2025/05/07/ethereum-activates-pectra-upgrade-raising-max-stake-to-2048-eth) — CoinDesk · evidence page: https://worldwiki.io/source/211
8. [Ethereum's energy usage will soon decrease by ~99.95%](https://blog.ethereum.org/2021/05/18/country-power-no-more) — Ethereum Foundation Blog · evidence page: https://worldwiki.io/source/212
9. [Ouroboros: A Provably Secure Proof-of-Stake Blockchain Protocol (Advances in Cryptology – CRYPTO 2017, pp. 357–388, doi:10.1007/978-3-319-63688-7_12)](https://www.research.ed.ac.uk/en/publications/ouroboros-a-provably-secure-proof-of-stake-blockchain-protocol/) — University of Edinburgh Research Explorer / Springer · evidence page: https://worldwiki.io/source/213
10. [Peercoin](https://en.wikipedia.org/wiki/Peercoin) — Wikipedia · evidence page: https://worldwiki.io/source/214
11. [Proof-of-stake — Octez & Protocol documentation](https://octez.tezos.com/docs/active/proof_of_stake.html) — Tezos / Octez documentation · evidence page: https://worldwiki.io/source/215
12. [Statement on Certain Protocol Staking Activities](https://www.sec.gov/newsroom/speeches-statements/statement-certain-protocol-staking-activities-052925) — U.S. Securities and Exchange Commission, Division of Corporation Finance · evidence page: https://worldwiki.io/source/216