CyberSecBulletin
CVE-2023-34109NVD status: Modified

zxcvbn: Uncontrolled Resource Consumption

CVE-2023-34109 is a high-severity uncontrolled resource consumption vulnerability in zxcvbn from Zxcvbn-ts, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected zxcvbn versions: < 3.0.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.5% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Zxcvbn-ts to 3.0.2 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Zxcvbn-tszxcvbn< 3.0.2Not stated
Zxcvbn-ts ProjectZxcvbn-tsbefore 3.0.23.0.2

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
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.16.5MediumCNA (github.com)
CVSS 3.17.5HighNVD

Official description

zxcvbn-ts is an open source password strength estimator written in typescript. This vulnerability affects users running on the nodeJS platform which are using the second argument of the zxcvbn function. It can result in an unbounded resource consumption as the user inputs array is extended with every function call. Browsers are impacted, too but a single user need to do a lot of input changes so that it affects the browser, while the node process gets the inputs of every user of a platform and can be killed that way. This problem has been patched in version 3.0.2. Users are advised to upgrade. Users unable to upgrade should stop using the second argument of the zxcvbn function and use the zxcvbnOptions.setOptions function.

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

The underlying weakness: Uncontrolled Resource Consumption

The product does not properly control the allocation and maintenance of a limited resource.

How developers prevent this class of flaw

  • Ensure that protocols have specific limits of scale placed on them.
  • Ensure that all failures in resource allocation place the system into a safe posture.

More Uncontrolled Resource Consumption vulnerabilities (CWE-400)

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

Recent Uncontrolled Resource Consumption vulnerabilities

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