CVE-2026-62162

Hydra is a layer-two scalability solution for Cardano. Prior to 2.1.0, the `Claim` branch in `hydra-plutus/validators/deposit.ak` checks only that `datum.head_id` matches the attacker-controlled `redeemer.currencySymbol` and that the transaction is valid before the deposit deadline. It neither requires spending the Head state-token UTxO in the same transaction nor constrains outputs. After a deposit made through `POST /commit` is confirmed, any third party able to build a Cardano transaction can observe and consume the pending deposit UTxO before its deadline and redirect the assets to an arbitrary address. A standalone deposit spend invokes no Head validator, bypassing its safety checks; historical head-ID binding and the Aiken rewrite retained this missing invariant. The default deadline is three times depositPeriod, so the described attack applies to pending deposits before that deadline. This issue is fixed in version 2.1.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/cardano-scaling/hydra/commit/ff60e4af4ecf05545a696a6d9bf1afeffe991de0
https://github.com/cardano-scaling/hydra/releases/tag/2.1.0
https://github.com/cardano-scaling/hydra/security/advisories/GHSA-gfpc-m687-p7h5

Configurations

No configuration.

History

30 Oct 2026, 19:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 19:18

Updated : 2026-10-30 23:17

NVD link : CVE-2026-62162

Mitre link : CVE-2026-62162

CVE.ORG link : CVE-2026-62162

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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