Input buffer over-read in AES-XTS implementation on 64 bit ARM

Vulnerability Description

Issue summary: The AES-XTS cipher decryption implementation for 64 bit ARM platform contains a bug that could cause it to read past the input buffer, leading to a crash. Impact summary: Applications that use the AES-XTS algorithm on the 64 bit ARM platform can crash in rare circumstances. The AES-XTS algorithm is usually used for disk encryption. The AES-XTS cipher decryption implementation for 64 bit ARM platform will read past the end of the ciphertext buffer if the ciphertext size is 4 mod 5 in 16 byte blocks, e.g. 144 bytes or 1024 bytes. If the memory after the ciphertext buffer is unmapped, this will trigger a crash which results in a denial of service. If an attacker can control the size and location of the ciphertext buffer being decrypted by an application using AES-XTS on 64 bit ARM, the application is affected. This is fairly unlikely making this issue a Low severity one.

References

• https://www.openssl.org/news/secadv/20230419.txt
• https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=bc2f61ad70971869b242fc1cb445b98bad50074a
• https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=02ac9c9420275868472f33b01def01218742b8bb
• https://security.netapp.com/advisory/ntap-20230908-0006/