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TI-2023-22613 Aliases CVE-2023-42448

Improper input validation in input-output-hk hydra

Priority LOW 37CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Hydra is the layer-two scalability solution for Cardano. Prior to version 0.13.0, the specification states that the contestation period in the datum of the UTxO at the head validator must stay unchanged as the state progresses from Open to Closed (Close transaction), but no such check appears to be performed in the `checkClose` function of the head validator. This would allow a malicious participant to modify the contestation deadline of the head to either allow them to fanout the head without giving another participant the chance to contest, or prevent any participant from ever redistributing the funds locked in the head via a fan-out. Version 0.13.0 contains a patch for this issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00977 62nd percentileScored 2026-11-07
Fix Fixed hydra (input-output-hk): 0.13.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
input-output-hkhydrabefore 0.13.00.13.0Patch availableCNA
  • hydra Vendorinput-output-hk Affected before 0.13.0 Fixed in 0.13.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:iohk:hydra:*:*:*:*:*:*:*:*before 0.13.0Vulnerableinput-output-hk
  • cpe:2.3:a:iohk:hydra:*:*:*:*:*:*:*:* Versions before 0.13.0 Vulnerable ·input-output-hk

Remediation

  • Fix · CNA hydra (input-output-hk) Fixed in 0.13.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-42448

References

Patch 1

Advisory 1

Other 3

  • TI-2023-20049 Hydra's committed UTxOs at Commit validator and UTxOs at Initial validator can be spent arbitrarily by anyone CVSS 3.1CRITICAL 9.1
  • TI-2023-22614 Improper input validation in input-output-hk hydra CVSS 3.1HIGH 8.1
  • TI-2023-22897 Snapshot signature not including HeadID will allow replay attacks CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences