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Hydra CVE-2023-42448

HIGH
Improper Input Validation (CWE-20)
2023-10-04 security-advisories@github.com
8.1
CVSS 3.1 · NVD
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Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V2 - Validation and Business Logic Input validation, allowlisting
Impact

CVSS score of 8.1 (HIGH). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.8% exploitation probability (EPSS)

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AnalysisAI

Hydra is the layer-two scalability solution for Cardano. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-20. 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. Affected products include: Iohk Hydra. Version information: version 0.13.0.

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Severity by source

NVD PRIMARY 8.1 HIGH
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

DescriptionNVD

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.

Threat Intelligence Overview

EPSS Score
0.8%
Top 48% exploitable
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.8%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
No
Human Impact· derived
Medium

Priority Score

41
Low Medium High Critical
KEV: 0
EPSS: +1
CVSS: +40
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)NVD

cpe:2.3:a:iohk:hydra:*:*:*:*:*:*:*:*

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