NULL Pointer Dereference

Summary

The libosdp is an implementation of IEC 60839-11-5 OSDP (Open Supervised Device Protocol) and provides a C library with support for C++, Rust, and Python3. In the file "ospd_common.c", within the "osdp_reply_name" function, any reply id between REPLY_ACK and REPLY_XRD is valid, but the names array does not declare all of the range. On a case of an undefined reply id within the range, the name will be null (name = names[reply_id - REPLY_ACK];). Null name will cause a crash on the next line: if (name[0] == '\0') as null[0] is invalid. As this logic is not limited to a secure connection, an attacker may trigger this vulnerability without any prior knowledge. This issue affects libosdp versions prior to 2.4.0.