CVE-2023-42448Hydra's contestation period in head datum can be modified during Close transaction, allowing malicious participant to freely modify the contestation deadline
- 8.1HighCVSS base score
- 0.98%Exploitation in 30 daysEPSS · top 37% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By GitHub_M
- 26 days later
· 26 days later
Published
- 12 months later
· 12 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.98% · top 37% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.
Affected products
- affected < 0.13.0
References
References5
- https://github.com/input-output-hk/hydra/security/advisories/GHSA-mgcx-6p7h-5996 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/input-output-hk/hydra/commit/2f45529729e28254a62f7a7c8d6649066923ed1f (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/input-output-hk/hydra/blob/master/CHANGELOG.md#0130---2023-10-03 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/input-output-hk/hydra/blob/master/hydra-plutus/src/Hydra/Contract/Head.hs#L284-L296 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/input-output-hk/hydra/blob/master/hydra-plutus/src/Hydra/Contract/Head.hs#L320-L323 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-46894 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-42448)Record last updated .