res/res_pjsip_exten_state.c in the PJSIP channel driver in Asterisk Open Source 12.x before 12.1.0 allows remote authenticated users to cause a denial of service (crash) via a SUBSCRIBE request without any Accept headers, which triggers an invalid pointer dereference.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.174
EPSS Ranking 94.7%