CyberSecBulletin
CVE-2023-30591NVD status: Modified

NodeBB: Improper Check for Unusual or Exceptional Conditions

Published Updated By the CyberSecBulletin desk

CVE-2023-30591 is a high-severity improper check for unusual or exceptional conditions vulnerability in NodeBB, 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 NodeBB versions: 2.8.10 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 58.7% chance of exploitation within 30 days, which is in the top 0.88% of all scored CVEs.

Patch now

Exploitation in the next 30 days is more likely than not, according to EPSS.

What to do

  1. Check which version of NodeBB you run against the affected versions below, and install the vendor's latest release.
  2. 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
NodeBBNodeBB2.8.10 and earlierNot 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
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 3.17.5HighCNA (starlabs.sg)
CVSS 3.17.5HighNVD

Official description

Denial-of-service in NodeBB <= v2.8.10 allows unauthenticated attackers to trigger a crash, when invoking `eventName.startsWith()` or `eventName.toString()`, while processing Socket.IO messages via crafted Socket.IO messages containing array or object type for the event name respectively.

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

The underlying weakness: Improper Check for Unusual or Exceptional Conditions

The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Choose languages with features such as exception handling that force the programmer to anticipate unusual conditions that may generate exceptions. Custom exceptions may need to be developed to handle unusual business-logic conditions. Be careful not to pass sensitive exceptions back to the user (CWE-209, CWE-248).
  • Check the results of all functions that return a value and verify that the value is expected.
  • If using exception handling, catch and throw specific exceptions instead of overly-general exceptions (CWE-396, CWE-397). Catch and handle exceptions as locally as possible so that exceptions do not propagate too far up the call stack (CWE-705). Avoid unchecked or uncaught exceptions where feasible (CWE-248).

More Improper Check for Unusual or Exceptional Conditions vulnerabilities (CWE-754)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in NodeBB

All NodeBB vulnerabilities

Recent Improper Check for Unusual or Exceptional Conditions vulnerabilities

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