CVE-2019-11231
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the...
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
9.8
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
- Record
CVE-2019-11231- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-22
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
- Record
CVE-2019-11231- Updated
- 2026-11-02
EUVDEUVD-2019-2930 No score
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
- Record
EUVD-2019-2930- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hx55-22f6-mp64
9.8
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the...
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
- Record
GHSA-hx55-22f6-mp64- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
OSV
9.8
An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can bypass authentication. To do so, they need to supply a cookie based on an SHA-1 computation of this known information. The vulnerability exists in the admin/theme-edit.php file. This file checks for forms submissions via POST requests, and for the csrf nonce. If the nonce sent is correct, then the file provided by the user is uploaded. There is a path traversal allowing write access outside the jailed themes directory root. Exploiting the traversal is not necessary because the .htaccess file is ignored. A contributing factor is that there isn't another check on the extension before saving the file, with the assumption that the parameter content is safe. This allows the creation of web accessible and executable files with arbitrary content.
- Record
CVE-2019-11231- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | GetSimpleCMS - Unauthenticated Remote Code Execution (Metasploit) | 2019-05-20 |
| Metasploit | GetSimpleCMS Unauthenticated RCE | 2019-04-28 |
| PoC in GitHub | akincibor/CVE-2019-11231-PoC | 2025-12-20 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, Exploit-DB, GitHub Advisories, Metasploit, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-11231 is a critical vulnerability (CVSS 9.8) in Get-simple Getsimple Cms, published May 22, 2019. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 71.6%, the 99th percentile. No source names a fixed version.