CPEs used by subscribers on the access network receive their individual configuration settings from a central GAPS instance. A CPE identifies itself by the MAC address of its WAN interface and a certain chk value (48bit) derived from the MAC. The algorithm used to compute the chk was disclosed by reverse engineering the CPEs firmware. As a result, it is possible to forge valid chk values for any given MAC address and therefore receive the configuration settings of other subscribers CPEs. The configuration settings often contain sensitive values, for example credentials (username/password) for VoIP services. This issue affects Genexis B.V. GAPS up to 7.2.
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Gaps | Genexis | * | 7.2 (excluding) |
There are many different kinds of mistakes that introduce information exposures. The severity of the error can range widely, depending on the context in which the product operates, the type of sensitive information that is revealed, and the benefits it may provide to an attacker. Some kinds of sensitive information include:
Information might be sensitive to different parties, each of which may have their own expectations for whether the information should be protected. These parties include:
Information exposures can occur in different ways:
It is common practice to describe any loss of confidentiality as an “information exposure,” but this can lead to overuse of CWE-200 in CWE mapping. From the CWE perspective, loss of confidentiality is a technical impact that can arise from dozens of different weaknesses, such as insecure file permissions or out-of-bounds read. CWE-200 and its lower-level descendants are intended to cover the mistakes that occur in behaviors that explicitly manage, store, transfer, or cleanse sensitive information.