Openssl » Openssl : Security Vulnerabilities, CVEs, (Gain Privilege)

Issue summary: The AES-SIV cipher implementation contains a bug that causes it to ignore empty associated data entries which are unauthenticated as a consequence. Impact summary: Applications that use the AES-SIV algorithm and want to authenticate empty data entries as associated data can be mislead by removing adding or reordering such empty entries as these are ignored by the OpenSSL implementation. We are currently unaware of any such applications. The AES-SIV algorithm allows for authentication of multiple associated data entries along with the encryption. To authenticate empty data the application has to call EVP_EncryptUpdate() (or EVP_CipherUpdate()) with NULL pointer as the output buffer and 0 as the input buffer length. The AES-SIV implementation in OpenSSL just returns success for such a call instead of performing the associated data authentication operation. The empty data thus will not be authenticated. As this issue does not affect non-empty associated data authentication and we expect it to be rare for an application to use empty associated data entries this is qualified as Low severity issue.

In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads. This can result in an OpenSSL crash. This issue is not considered to be exploitable beyond a DoS.

OpenSSL before 1.0.0c, when J-PAKE is enabled, does not properly validate the public parameters in the J-PAKE protocol, which allows remote attackers to bypass the need for knowledge of the shared secret, and successfully authenticate, by sending crafted values in each round of the protocol.

OpenSSL, probably 0.9.6, does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack, a related issue to CVE-2002-0970.

The CMS_verify function in OpenSSL 0.9.8h through 0.9.8j, when CMS is enabled, does not properly handle errors associated with malformed signed attributes, which allows remote attackers to repudiate a signature that originally appeared to be valid but was actually invalid.