An Integer Signedness issue (for a return code) in the res_pjsip_sdp_rtp module in Digium Asterisk versions 15.7.1 and earlier and 16.1.1 and earlier allows remote authenticated users to crash Asterisk via a specially crafted SDP protocol violation.
Asterisk Project Security Advisory - When Asterisk makes an outgoing call, a very specific SDP protocol violation by the remote party can cause Asterisk to crash.