> CVE-2023-32887: Mediatek Baseband Unbounded Recursion Leading to Stack Overflow During Handling SIP Comments

An attacker sending a malformed SIP message over VoLTE to a device with a Mediatek baseband can trigger the vulnerability described here. The impact is unbounded recursion based stack overflow in the baseband, triggered by malformed VoLTE message such as SIP INVITE or MESSAGE request. The vulnerability described in this advisory affected a wide range of Mediatek devices. The January 2024 issue of the Mediatek Security Bulletin contains this vulnerability as CVE-2023-32887. Vulnerability Details When a SIP message is unpacked by sip_msg_unpack, inet_msg_unpack_header is called to parse the various MIME headers. This function inet_msg_mime_skip_comment is reached from inet_msg_mime_skipws (and other inet_msg_skipcfws* functions) and it recursively seeks over the comments from the header in order to remove white-spaces around and comments from the MIME header values.