CVEvulnerability
CVE-2019-12831
7.2 HIGH
Official page ↗
- Status
- Modified
- Published
- 2019-06-15
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.0 ([email protected])
- 7.2 HIGH — CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- CVSS 2.0 ([email protected])
- 6.5 MEDIUM — AV:N/AC:L/Au:S/C:P/I:P/A:P
- Weaknesses
- CWE-20
Description
In MyBB before 1.8.21, an attacker can abuse a default behavior of MySQL on many systems (that leads to truncation of strings that are too long for a database column) to create a PHP shell in the cache directory of a targeted forum via a crafted XML import, as demonstrated by truncation of aaaaaaaaaaaaaaaaaaaaaaaaaa.php.css to aaaaaaaaaaaaaaaaaaaaaaaaaa.php with a 30-character limit, aka theme import stylesheet name RCE.
Affected configurations
• mybb mybb (< 1.8.21)
Related
Weakness · CWE (1)
- CWE-20 Improper Input Validation weakness
References
- https://blog.mybb.com/2019/06/10/mybb-1-8-21-released-security-maintenance-release/ Release Notes, Vendor Advisory
- https://blog.ripstech.com/2019/mybb-stored-xss-to-rce/ Exploit, Vendor Advisory
- https://blog.mybb.com/2019/06/10/mybb-1-8-21-released-security-maintenance-release/ Release Notes, Vendor Advisory
- https://blog.ripstech.com/2019/mybb-stored-xss-to-rce/ Exploit, Vendor Advisory