Is Solana Secure? Network, Client and Application Risk

By Owen Thurm Published November 6, 2026 6 min read

Quick answer. It depends on the layer. Solana's last recorded halt was February 2024, and on November 6, 2026, its RPC showed about 82% of stake on Agave-based clients. The largest losses came from applications and keys, not the protocol.

Watch: Is Solana Secure? Network, Client and Application Risk 1:48

Video transcript

Is Solana secure enough for institutions? It depends on the layer. The largest losses came from applications and keys, not the protocol.

Start with the network. Solana's post-mortems describe seven halts or restarts through February 2024, lasting about four and a half to twenty hours. No later halt appears in the archive.

A bug shared by most validators can stop the chain. On November 6, 2026, about 82 percent of stake ran Agave-based clients, and about 16 percent Firedancer.

Stake is concentrated too. Eight validators held over 20 percent, the adversarial share Alpenglow's Votor is built to tolerate.

The largest losses sit above the protocol. A Wormhole program bug cost 326 million dollars, Mango Markets left 115 million in bad debt, and pre-signed admin transactions at Drift cost about 285 million.

Many controls are readable onchain. Upgrade authority lets a program change, mint authority creates supply, freeze authority freezes holders, and durable nonces keep signed transactions valid.

For risk teams, the checklist is practical. Plan for halts, credit on finalized, and spread stake by client. Read every authority, ban pre-signed admin actions, and keep keys in hardware.

On Solana, Guardian has run nine engagements for Jupiter since November 2025, and Managed Security reviews every multisig transaction before it is signed.

Read the full guide, or talk to Guardian at guardian.security before Solana reaches your risk committee.

Institutions weighing Solana need two separate answers. Is the network reliable? And are the programs, wallets and keys on it sound?

This guide gives no verdict. It separates network risk from application risk, dates each event to its source, and ends with controls a risk team can adopt.

For the wider picture, see Can a blockchain be hacked?

Consensus and Outage History

Solana's post-mortems describe liveness failures. The chain stopped or slowed, and validators restarted it.

Date	Cause, per the post-mortem	Duration
Dec 4, 2020	One validator sent different blocks for one slot	About 6 hours
Sep 14, 2021	Bots flooded a Raydium IDO; validators ran out of memory	About 17 hours
Apr 30, 2022	NFT mint bots sent 6 million transactions per second	About 7 hours
Jun 1, 2022	A durable nonce runtime bug	About 4.5 hours
Sep 30, 2022	Duplicate blocks hit a fork-choice bug	About 8 hours
Feb 25, 2023	An oversized block looped through forwarding services	About 20 hours degraded
Feb 6, 2024	An infinite loop in the program cache	About 5 hours

Restarts are a coordination job. In September 2021, restarting needed at least 80% of active stake to agree. The Foundation said "no funds were lost."

After the 2022 bot floods, Solana rolled out QUIC, stake-weighted quality of service and local fee markets. No later halt appears in the Foundation's post-mortem archive.

Alpenglow

On October 21, 2026, Solana replaced TowerBFT voting with Votor, the first phase of Alpenglow. It targets about 150ms finality, down from 12.8 seconds.

Votor tolerates 20% of adversarial stake plus 20% offline. TowerBFT's line was one-third faulty stake.

Rotor, the second phase, is not yet scheduled. Alpenglow had run on mainnet for 16 days when we wrote this.

Client Diversity and Firedancer

A bug shared by most validators can stop the chain.

In February 2024, over 95% of stake ran one release line. Nearly all validators stalled on the same block, Anza's report says.

We matched the client each validator reports in gossip to its stake. The data comes from Solana's public RPC.

Client family	Share of stake, Nov 6, 2026
Agave and clients built on it (Jito, Harmonic, BAM)	About 82%
Firedancer-based	About 16%
Other or unreported	About 1%

Firedancer's README says it "is written from scratch," bringing client diversity and resilience "to supply chain attacks in build tooling or dependencies."

Its first full mainnet release shipped on August 4, 2026. Earlier mainnet releases were Frankendancer, "a hybrid of the Agave validator and Firedancer's network components."

Firedancer was not supported for the Alpenglow switch, so its operators had to move to an Agave-based client. Firedancer v26.10.2 runs Alpenglow, but not the switch itself.

Validator concentration

In the same read, 696 vote accounts held 434.9 million SOL. The largest held 3.9%.

Eight validators together held over 20% of stake, the adversarial share Votor is built to tolerate. Eighteen held over one-third.

Coordinated patches

In April 2025, a researcher showed that forged proofs could pass Solana's ZK ElGamal Proof program, which could allow unlimited minting of confidential tokens.

Engineers sent patches to validator operators directly. A supermajority of stake ran them two days after the report, and the Foundation said there was no known exploit.

A second bug in June 2025 led engineers to disable confidential transfers in Token-2022 through a multisig upgrade.

When we read it over RPC on November 6, 2026, Token-2022 still had an upgrade authority.

Application-Layer Risk

The largest losses on record sit above the protocol:

Date	Incident	Layer	Impact
Feb 2022	Wormhole: forged signature set minted 120k whETH	Program bug	$326M, per Rekt
Aug 2, 2022	Slope wallet leaked key material	Wallet	About $4.1M, 9,231 wallets
Oct 2022	Mango Markets: MNGO price pushed up	Market design	$115M bad debt, per Rekt
Dec 3, 2024	@solana/web3.js publishing account compromised	Supply chain	Two malicious versions
Apr 1, 2026	Drift admin taken via pre-signed transactions	Keys and signers	About $285M, per Chainalysis

Wormhole's program did not correctly verify an account it was given, Rekt reported. That account check is the classic Solana bug in our Solana program security guide.

Slope's app sent private key material to an application monitoring service. The Foundation said it "was not a protocol-level vulnerability."

The web3.js versions stole keys from apps that handle them directly. The advisory says non-custodial wallets should not be affected.

At Drift, attackers got two of five council signers to pre-sign durable nonce transactions, per Chainalysis. Our Drift breakdown covers how.

The ecosystem response

In April 2026, the Solana Foundation launched STRIDE: protocol evaluations by Asymmetric Research, with findings published.

Passing protocols over $10M TVL get funded threat monitoring, and those over $100M get formal verification. SIRN, a network of security firms, handles incident response.

Keys, Upgrades and Operations

Many Solana controls sit in authorities anyone can read onchain:

Upgrade authority: while set, the program can change. Setting it to None makes it immutable.
Mint authority: can create new supply of a token.
Freeze authority: can freeze any account holding that token.
Durable nonces: keep a signed transaction valid until the nonce advances.

The Foundation plans to remove durable nonces, roughly six months after a replacement is ready. No date is set.

Our USDT guide read USDT's Solana mint and freeze authority on November 6, 2026: a 2-of-3 multisig.

Institutional Control Checklist

Plan for halts. Past outages ran about 4.5 to 20 hours. Define how you pause and reconcile.
Credit on finalized. Under Alpenglow, confirmed and finalized now describe the same state; read finalized.
Spread stake by client. Delegate across validators running different client families.
Read every authority. Upgrade, mint and freeze, for each program and token you touch. Alert on changes.
Ban pre-signed admin actions. No durable nonces for council signers; watch their nonce accounts.
Pin dependencies. Lock SDK versions and review every update before it ships.
Keep keys in hardware. The Foundation said Slope did not affect hardware wallets.
Ask each protocol for evidence. Its STRIDE evaluation, audit reports and upgrade authority.
Track advisories. Agave and Firedancer releases, and Solana Foundation post-mortems.

Our blockchain security risks guide maps the same layers across chains.

How Guardian Helps

Guardian's institutional practice covers target architecture: which chain and why, the custody and signing model, and the upgrade and pause paths you will need.

The protocols, bridges and custodians you depend on are assessed "as concentrations of risk rather than as logos on a slide."

On Solana, Guardian has run nine engagements for Jupiter since November 2025. Managed Security reviews every multisig transaction before it is signed.

Frequently Asked Questions

Is Solana more secure than Ethereum?

They make different trade-offs. Compare validators needed to pass a fifth or a third of stake, client share, and halt history. On November 6, 2026, Solana's RPC showed 8 validators with over 20% of stake.

How many times has Solana gone down?

Solana's post-mortems cover seven halts or restarts, from December 2020 to February 2024. The longest full halt, in September 2021, lasted about 17 hours. No later halt appears in the archive.

What is Firedancer?

Firedancer is a Solana validator client from Jump Crypto, written from scratch, not built on Agave. Its first full mainnet release shipped on August 4, 2026. On November 6, 2026, gossip data showed Firedancer-based clients with about 16% of stake.

What is Alpenglow?

Alpenglow is Solana's new consensus protocol. Its first phase, Votor, went live on October 21, 2026, targeting about 150ms finality. It tolerates 20% adversarial stake plus 20% offline stake. Its second phase, Rotor, is not yet scheduled.

Sources

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