XWiki Commons are technical libraries common to several other top level XWiki projects. Starting in version 3.1-milestone-1, any user can edit their own profile and inject code, which is going to be executed with programming right. The same vulnerability can also be exploited in all other places where short text properties are displayed, e.g., in apps created using Apps Within Minutes that use a short text field. The problem has been patched on versions 13.10.9, 14.4.4, 14.7RC1.
Weakness
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as escape, meta, or control character sequences when they are sent to a downstream component.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Commons |
Xwiki |
3.2 (including) |
13.10.9 (excluding) |
| Commons |
Xwiki |
14.4 (including) |
14.4.4 (excluding) |
| Commons |
Xwiki |
14.5 (including) |
14.7 (excluding) |
| Commons |
Xwiki |
3.1-milestone1 (including) |
3.1-milestone1 (including) |
| Commons |
Xwiki |
3.1-milestone2 (including) |
3.1-milestone2 (including) |
| Commons |
Xwiki |
3.1.1 (including) |
3.1.1 (including) |
| Commons |
Xwiki |
14.4-rc1 (including) |
14.4-rc1 (including) |
Potential Mitigations
- Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
References