Exit-Only Pools

Overview

astroport-pair-exit-only is the code a pool is migrated to when it must only allow balanced withdrawals. It was written for the six Neutron pools drained in the 2026-09-22 incident. Their balances had gone to zero while their LP supply was unchanged, so a small deposit would have minted almost all LP tokens and taken the refill, and swaps would have traded the refill at stale prices. The pools were migrated to this code, then refilled with the returned assets, so their LPs can withdraw their share.

An exit-only pool:

• pays an LP its share of every asset the pool holds, rounded down, and burns the LP tokens;
• refuses deposits, swaps, config and ownership changes, and any other CW20 hook;
• answers the pair, pool, share and simulate_withdraw queries; every other query returns an exit-only error.

The migration doesn't write anything: the pool keeps its storage and its cw2 version, so a later build of its original contract that accepts that version could take it back.

NOTE

LP tokens staked in the Incentives contract must be unstaked before they can be withdrawn.

Pools running this code (Neutron)

Pool	Address	Pool contract before the migration	LP token
dATOM/USDC	neutron1nfns3ck2ykrs0fknckrzd9728cyf77devuzernhwcwrdxw7ssk2s3tjf8r	pair-concentrated-duality 4.3.1	native
NTRN/USDC	neutron18c8qejysp4hgcfuxdpj4wf29mevzwllz5yh8uayjxamwtrs0n9fshq9vtv	pair-concentrated-duality 4.3.1	native
dATOM/ATOM	neutron1yem82r0wf837lfkwvcu2zxlyds5qrzwkz8alvmg0apyrjthk64gqeq2e98	pair-concentrated 4.0.2	native
USDC/DYDX	neutron1j4xpv03fw664mvntlhqnzp5hjqk2nfw00vrgx9qlq97rxc9fu3lqvmszl2	pair-concentrated 1.2.13	CW20
wstETH/WETH	neutron1yw0a7nxa8jdgzmdsme4gwxhj76n44z305qgwrzvlfavgna9epcys3k9m2f	pair-concentrated 1.2.15	CW20
axlUSDC/USDC	neutron1ns2tcunrlrk5yk62fpl74ycazanceyfmmq7dlj6sq8n0rnkuvk7szstkyx	pair-transmuter 1.0.0	CW20

Links

• Contract Repo: https://github.com/astroport-fi/astroport-core/tree/main/contracts/pair_exit_only
• contract.rs: https://github.com/astroport-fi/astroport-core/blob/main/contracts/pair_exit_only/src/contract.rs
• Tests: https://github.com/astroport-fi/astroport-core/tree/main/contracts/pair_exit_only/tests
• Version: astroport-pair-exit-only 1.0.0

InstantiateMsg

None. The code can't be instantiated; pools can only be migrated to it.

MigrateMsg

The migrate message is empty. Supported pool contracts are astroport-pair-concentrated (1.x and 4.x), astroport-pair-concentrated-duality and astroport-pair-transmuter. Migration is refused for other contracts, for a config that names another address, and for a pool already in pair_concentrated 4.3's exit-only mode (which withholds an asset). Migrating again changes nothing.

json

contract.rs

_1

{}

ExecuteMsg

withdraw_liquidity

For pools with a native (tokenfactory) LP token. Attach the LP tokens as funds, for example factory/neutron18c8qejysp4hgcfuxdpj4wf29mevzwllz5yh8uayjxamwtrs0n9fshq9vtv/astroport/share for NTRN/USDC. The examples below use that pool. assets must be empty, and the call fails if the share would receive nothing.

json

pair.rs

_23

{

_23

"withdraw_liquidity": {

_23

"assets": [],

_23

"min_assets_to_receive": [

_23

{

_23

"info": {

_23

"native_token": {

_23

"denom": "untrn"

_23

}

_23

},

_23

"amount": "990000"

_23

},

_23

{

_23

"info": {

_23

"native_token": {

_23

"denom": "ibc/B559A80D62249C8AA07A380E2A2BEA6E5CA9A6F079C912C3A9E9B494105E4F81"

_23

}

_23

},

_23

"amount": "1200000"

_23

}

_23

]

_23

}

_23

}

Params	Type	Description
assets	Vec<Asset>	Must be empty. One-sided withdrawals are refused
min_assets_to_receive	Option<Vec<Asset>>	Fails the withdrawal if less than these amounts would be returned

receive

For pools with a CW20 LP token (USDC/DYDX, wstETH/WETH and axlUSDC/USDC). Execute send on the LP token contract with the pool as contract and a base64-encoded withdraw_liquidity hook. The hook takes the same fields as above, and any other hook is refused.

json

_7

{

_7

"send": {

_7

"contract": "neutron1j4xpv03fw664mvntlhqnzp5hjqk2nfw00vrgx9qlq97rxc9fu3lqvmszl2",

_7

"amount": "1000000",

_7

"msg": "eyJ3aXRoZHJhd19saXF1aWRpdHkiOnt9fQ=="

_7

}

_7

}

Params	Type	Description
contract	String	The pool address (here USDC/DYDX)
amount	Uint128	The amount of LP tokens to withdraw
msg	Binary	Base64 of {"withdraw_liquidity":{}}

QueryMsg

pair

Returns the pool's PairInfo, unchanged by the migration.

json

_3

{

_3

"pair": {}

_3

}

pool

Returns the assets the pool holds and the LP supply, as a PoolResponse.

json

_3

{

_3

"pool": {}

_3

}

json

_21

{

_21

"assets": [

_21

{

_21

"info": {

_21

"native_token": {

_21

"denom": "untrn"

_21

}

_21

},

_21

"amount": "1000000000"

_21

},

_21

{

_21

"info": {

_21

"native_token": {

_21

"denom": "ibc/B559A80D62249C8AA07A380E2A2BEA6E5CA9A6F079C912C3A9E9B494105E4F81"

_21

}

_21

},

_21

"amount": "1200000000"

_21

}

_21

],

_21

"total_share": "500000000"

_21

}

Params	Type	Description
assets	Vec<Asset>	The pool's balance of each of its assets
total_share	Uint128	The LP tokens in circulation

share and simulate_withdraw

Both return what a given amount of LP tokens would be withdrawn for, as a Vec<Asset>.

json

_5

{

_5

"simulate_withdraw": {

_5

"lp_amount": "1000000"

_5

}

_5

}

Params	Type	Description
lp_amount	Uint128	The amount of LP tokens (amount for share)