CVE-2024-23336
Incomplete disallowed remote addresses list in MyBB
CVE-2024-23336 is a medium vulnerability (CVSS 5.0) in Mybb, published May 1, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.46%, the 40th percentile. No source names a fixed version.
- Severity
- 5.0 MediumCVSS 3.1, CVE List
- Exploit chance
- 0.46%EPSS, 40th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
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 ($config['disallowed_remote_addresses']) contains the address 127.0.0.1, but does not include the complete block 127.0.0.0/8. MyBB 1.8.38 resolves this issue in default installations. Administrators of installed boards should update the existing configuration (inc/config.php) to include all addresses blocked by default. Additionally, users are advised to verify that it includes any other IPv4 addresses resolving to the server and other internal resources. Users unable to upgrade may manually add 127.0.0.0/8' to their disallowed address list.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
Affected products
What each source reports
CVE List Score used
Incomplete disallowed remote addresses list in MyBB
MyBB is a free and open source forum software. The default list of disallowed remote hosts does not contain the 127.0.0.0/8 block, which may result in a Server-Side Request Forgery (SSRF) vulnerability. The Configuration File's Disallowed Remote Addresses list ($config['disallowed_remote_addresses']) 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.
- Record
CVE-2024-23336- CVSS 3.1
- 5.0 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-918, CWE-184
- Updated
- 2026-11-02
EUVDEUVD-2024-20847
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 ($config['disallowed_remote_addresses']) contains the address 127.0.0.1, but does not include the complete block 127.0.0.0/8. MyBB 1.8.38 resolves this issue in default installations. Administrators of installed boards should update the existing configuration (inc/config.php) to include all addresses blocked by default. Additionally, users are advised to verify that it includes any other IPv4 addresses resolving to the server and other internal resources. Users unable to upgrade may manually add 127.0.0.0/8' to their disallowed address list.
- Record
EUVD-2024-20847- CVSS 3.1
- 5.0 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-03
NVD
MyBB is a free and open source forum software. The default list of disallowed remote hosts does not contain the 127.0.0.0/8 block, which may result in a Server-Side Request Forgery (SSRF) vulnerability. The Configuration File's Disallowed Remote Addresses list ($config['disallowed_remote_addresses']) 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.
- Record
CVE-2024-23336- CVSS 3.1
- 5.0 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-184, CWE-918
- Updated
- 2026-11-02
OSV
Incomplete disallowed remote addresses list in MyBB
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']) 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.
- Record
CVE-2024-23336- CVSS 3.1
- 5.0 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-184, CWE-918
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
github.com/mybb/mybb/security/advisories/GHSA-qfrj-65mv-h75h
docs.mybb.com/1.8/administration/configuration-file
mybb.com/versions/1.8.38
nvd.nist.gov/vuln/detail/CVE-2024-23336