CyberSecBulletin
CVE-2023-42448NVD status: Modified

hydra: Improper Validation of Specified Quantity in Input

CVE-2023-42448 is a high-severity improper validation of specified quantity in input vulnerability in hydra from Input-output-hk, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected hydra versions: < 0.13.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.98% chance of exploitation within 30 days, higher than 63% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of hydra you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Input-output-hkhydra< 0.13.0Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.1HighCNA (github.com)
CVSS 3.18.1HighNVD

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Validation of Specified Quantity in Input

The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.

More Improper Validation of Specified Quantity in Input vulnerabilities (CWE-1284)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in hydra

All hydra vulnerabilities

Recent Improper Validation of Specified Quantity in Input vulnerabilities

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