There is an overflow bug in the AVX2 Montgomery multiplication procedure used in exponentiation with 1024-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH1024 are considered just feasible, because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH1024 private key among multiple clients, which is no longer an option since CVE-2016-0701. This only affects processors that support the AVX2 but not ADX extensions like Intel Haswell (4th generation). Note: The impact from this issue is similar to CVE-2017-3736, CVE-2017-3732 and CVE-2015-3193. OpenSSL version 1.0.2-1.0.2m and 1.1.0-1.1.0g are affected. Fixed in OpenSSL 1.0.2n. Due to the low severity of this issue we are not issuing a new release of OpenSSL 1.1.0 at this time. The fix will be included in OpenSSL 1.1.0h when it becomes available. The fix is also available in commit e502cc86d in the OpenSSL git repository.
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 |
|---|---|---|---|
| Openssl | Openssl | 1.0.2 (including) | 1.0.2 (including) |
| Openssl | Openssl | 1.0.2-beta1 (including) | 1.0.2-beta1 (including) |
| Openssl | Openssl | 1.0.2-beta2 (including) | 1.0.2-beta2 (including) |
| Openssl | Openssl | 1.0.2-beta3 (including) | 1.0.2-beta3 (including) |
| Openssl | Openssl | 1.0.2a (including) | 1.0.2a (including) |
| Openssl | Openssl | 1.0.2b (including) | 1.0.2b (including) |
| Openssl | Openssl | 1.0.2c (including) | 1.0.2c (including) |
| Openssl | Openssl | 1.0.2d (including) | 1.0.2d (including) |
| Openssl | Openssl | 1.0.2e (including) | 1.0.2e (including) |
| Openssl | Openssl | 1.0.2f (including) | 1.0.2f (including) |
| Openssl | Openssl | 1.0.2g (including) | 1.0.2g (including) |
| Openssl | Openssl | 1.0.2h (including) | 1.0.2h (including) |
| Openssl | Openssl | 1.0.2i (including) | 1.0.2i (including) |
| Openssl | Openssl | 1.0.2j (including) | 1.0.2j (including) |
| Openssl | Openssl | 1.0.2k (including) | 1.0.2k (including) |
| Openssl | Openssl | 1.0.2l (including) | 1.0.2l (including) |
| Openssl | Openssl | 1.0.2m (including) | 1.0.2m (including) |
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.