Security Resilience

CVE-2024-23336

SSRF in Mybb ≤ 1.8.38

Published
01 May 2024
Modified
30 June 2025
Patch / advisory
CVSS Score v3.1 5.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS Score 0.0046 38th percentile
Risk Priority 40 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

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, exploitation aligns with the MITRE ATT&CK technique LSASS Memory (T1003.001); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-4 (Information Flow Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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

MITRE ATT&CK Enterprise Techniques

T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
T1003.005 Cached Domain Credentials Credential Access
Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
T1016.001 Internet Connection Discovery Discovery
Adversaries may check for Internet connectivity on compromised systems.
T1021.001 Remote Desktop Protocol Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-29458Same product: Mybb Mybb
CVE-2025-29459Same product: Mybb Mybb
CVE-2025-29457Same product: Mybb Mybb
CVE-2025-29460Same product: Mybb Mybb
CVE-2025-48940Same product: Mybb Mybb
CVE-2023-53979Same product: Mybb Mybb
CVE-2023-41362Same product: Mybb Mybb
CVE-2025-48941Same product: Mybb Mybb
CVE-2023-53977Same product: Mybb Mybb
CVE-2023-46251Same product: Mybb Mybb

Affected Assets

mybb
mybb
≤ 1.8.38

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)
  • V3.5.2
  • V4.4.2
  • V16.2.5
  • V1.3.6

Mitigating Controls (NIST 800-53 r5) AI

Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.

SI-10 requires validity checks on inputs, which structurally replaces incomplete deny-lists with complete allow-list or sanitization logic.

Boundary protection limits the network reach of server-initiated requests even if SSRF occurs.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

DE.CM-09 partial match
blocks

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
blocks

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.IR-01 partial match
blocks

Network segmentation and egress controls can limit the damage from successful SSRF requests.

PR.PS-06 partial match
blocks

Secure SDLC practices directly require complete, positive input validation instead of incomplete denylists.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

removes
removes
removes
removes

References