Improper serialization of internal state in the authorization subsystem in MongoDB Servers authorization subsystem permits a user with valid credentials to bypass IP whitelisting protection mechanisms following administrative action. This issue affects MongoDB Server v4.2 versions prior to 4.2.3; MongoDB Server v4.0 versions prior to 4.0.15; MongoDB Server v4.3 versions prior to 4.3.3and MongoDB Server v3.6 versions prior to 3.6.18.
Weakness
The product filters data in a way that causes it to be reduced or “collapsed” into an unsafe value that violates an expected security property.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Mongodb |
Mongodb |
3.6.0 (including) |
3.6.18 (excluding) |
| Mongodb |
Mongodb |
4.0.0 (including) |
4.0.15 (excluding) |
| Mongodb |
Mongodb |
4.2.0 (including) |
4.2.3 (excluding) |
| Mongodb |
Mongodb |
4.3.0 (including) |
4.3.3 (excluding) |
| Mongodb |
Ubuntu |
bionic |
* |
| Mongodb |
Ubuntu |
eoan |
* |
| Mongodb |
Ubuntu |
trusty |
* |
| Mongodb |
Ubuntu |
trusty/esm |
* |
| Mongodb |
Ubuntu |
xenial |
* |
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