Cyber Resilience

CVE-2024-23336

Medium

Published: 01 May 2024

Published
01 May 2024
Modified
30 June 2025
KEV Added
Patch
CVSS Score v3.1 5.0 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS Score 0.0014 34.6th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-23336 is a medium-severity Incomplete List of Disallowed Inputs (CWE-184) vulnerability in Mybb Mybb. Its CVSS base score is 5.0 (Medium).

Operationally, ranked at the 34.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

MyBB is a free and open source forum software. The default list of disallowed remote hosts does not contain the `127.0.0.0/8` block, which may result in a Server-Side Request Forgery (SSRF) vulnerability. The Configuration File's _Disallowed Remote Addresses_ list (`$config['disallowed_remote_addresses']`)…

more

contains the address `127.0.0.1`, but does not include the complete block `127.0.0.0/8`. MyBB 1.8.38 resolves this issue in default installations. Administrators of installed boards should update the existing configuration (`inc/config.php`) to include all addresses blocked by default. Additionally, users are advised to verify that it includes any other IPv4 addresses resolving to the server and other internal resources. Users unable to upgrade may manually add 127.0.0.0/8' to their disallowed address list.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

mybb
mybb
≤ 1.8.38

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-918

Penetration testing attempts server-side requests to internal resources, identifying SSRF weaknesses for remediation.

addresses: CWE-918

Outbound connections to external resources can be monitored and limited at the boundary, reducing SSRF impact.

addresses: CWE-918

Validates server-side URLs and resource references to block SSRF attempts.

addresses: CWE-918

Detects server-side request forgery through monitoring of unexpected outbound connections.

addresses: CWE-184

Spam filters rely on evolving blacklists, signatures, and heuristics of disallowed message patterns; keeping them updated per the control directly mitigates incomplete disallowed-input lists.

References