CVE-2023-0215

A use-after-free vulnerability was found in OpenSSL's BIO_new_NDEF function. The public API function BIO_new_NDEF is a helper function used for streaming ASN.1 data via a BIO. It is primarily used internally by OpenSSL to support the SMIME, CMS, and PKCS7 streaming capabilities, but it may also be called directly by end-user applications. The function receives a BIO from the caller, prepends a new BIO_f_asn1 filter BIO onto the front of it to form a BIO chain, and then returns the new head of the BIO chain to the caller. Under certain conditions. For example, if a CMS recipient public key is invalid, the new filter BIO is freed, and the function returns a NULL result indicating a failure. However, in this case, the BIO chain is not properly cleaned up, and the BIO passed by the caller still retains internal pointers to the previously freed filter BIO. If the caller then calls BIO_pop() on the BIO, a use-after-free will occur, possibly resulting in a crash.

This flaw was found in the OpenSSL library within the BIO_new_NDEF function, which is used for ASN.1 data streaming. The flaw is a use-after-free issue that happens when an error occurs while setting up a BIO chain. In this case, the filter BIO is freed, but the original BIO still holds a reference to it. If the caller later calls BIO_pop(), it tries to use this freed pointer, causing a crash and leading to a Denial of Service (DoS). The flaw is rated as moderate because it results in a crash but does not allow code execution, memory corruption beyond the crash, or data leakage.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.