CVE-2007-5640

CVE-2007-5640 describes a denial-of-service vulnerability affecting various Nortel IP telephony products, including the UNIStim IP Softphone 2050 and IP Phone 1140E. Attackers can block calls and force device re-registration by sending spoofed resume messages to the Signaling Server. This vulnerability has a CVSS score of 7.1, indicating high severity, as it can be exploited remotely with medium attack complexity, leading to a complete denial of availability. There is no evidence of active exploitation, publicly available exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this CVE.