Token-2022 extensions and rug risk
6 min read
Short answer: Token-2022 is Solana’s newer token program, and it lets a token carry optional extensions. Most are legitimate features — but a few hand the issuer ongoing power over tokens you already own: to intercept your transfers, take them outright, tax them, or leave your account frozen by default. Extensions themselves are not a scam signal. The question is which ones are enabled, and whether their authorities were given up.
Why this is different from a normal SPL token
With a classic SPL token, the issuer’s ongoing powers are basically two: mint more supply, and freeze accounts (see
mint & freeze authority). Token-2022 widens that surface. The extensions are set at mint creation and some remain configurable afterwards, so “the contract is standard” is no longer a complete answer.
The extensions that carry real risk
Permanent delegate — the most severe. It designates an address with standing authority to transfer or burn tokens from any holder’s account. If it is set to a party you don’t trust, your balance is not really yours: it can be moved or destroyed without your signature. There are legitimate uses (regulated assets, confiscation-by-design), but on a memecoin it is very hard to justify.
Transfer hook — the token points at a program that runs on every transfer. That program can reject transfers, which is the clean way to build a honeypot: buys succeed, sells get rejected, and the token looks liquid right up until you try to exit. Note this is the Solana analogue of the EVM hook pattern discussed in liquidity locks and rug risk — same idea, different chain: custom code sits in the path of your exit.
Transfer fee — a percentage skimmed on every transfer. Reasonable at 1–2%; a trap if the fee authority is still live and can raise it. A fee set high enough is functionally a sell block, without ever needing to touch liquidity.
Default account state = frozen — new holder accounts start frozen, so every buyer needs the issuer to thaw them before they can move anything. Whether you can sell becomes a permission the issuer grants, and can withhold.
Non-transferable — the token cannot be moved at all. Legitimate for soulbound/credential tokens, disqualifying for anything you intend to trade.
The pattern to internalise
Every risky extension above is a variation on one theme: someone other than you sits in the path of your exit. That is the same question as “can the deployer pull the liquidity?” — just moved from the pool into the token itself. When you evaluate a Token-2022 mint, you are really asking: after I buy, who can still interfere with my ability to sell?
How to check
Any Solana explorer will list a mint’s extensions. For each one that is enabled, ask the follow-up that actually matters — is the corresponding authority still held, or was it revoked? An extension with a live authority is an ongoing power; the same extension with a revoked authority is frozen in its current configuration. Specifically: is there a permanent delegate at all; does a transfer hook point at a verified, non-upgradeable program; can the transfer fee still be raised; and is the default account state frozen?
What extensions can’t tell you
A perfectly clean extension set does not make a token safe. It removes some mechanical traps; it says nothing about the far more common outcomes. Across the
launches we track, most tokens don’t die from an exotic extension — they die from concentrated supply being dumped, or from simply being abandoned. Contract-level checks are table stakes, which is precisely why they don’t differentiate much: nearly every launch passes them.
What we measure instead
Soliscope scores the
creator, because that is what our data shows actually predicts. On tracked pump.fun launches, a creator who has rugged before goes on to rug
~2.3× more often than the baseline — measured with no hindsight, and published with its caveats on
our methodology page. Check the extensions to rule out mechanical traps, then check
who created the token to judge the likelier risk.