Asterisk PBX Crashes with SEGV When Sending SIP Requests to Certain URIs
CVE-2024-42491
What is CVE-2024-42491?
Asterisk is an open-source private branch exchange (PBX). Prior to versions 18.24.3, 20.9.3, and 21.4.3 of Asterisk and versions 18.9-cert12 and 20.7-cert2 of certified-asterisk, if Asterisk attempts to send a SIP request to a URI whose host portion starts with .1 or [.1], and res_resolver_unbound is loaded, Asterisk will crash with a SEGV. To receive a patch, users should upgrade to one of the following versions: 18.24.3, 20.9.3, 21.4.3, certified-18.9-cert12, certified-20.7-cert2. Two workarounds are available. Disable res_resolver_unbound by setting noload = res_resolver_unbound.so in modules.conf, or set rewrite_contact = yes on all PJSIP endpoints. NOTE: This may not be appropriate for all Asterisk configurations.
Affected Version(s)
asterisk < 18.24.3 < 18.24.3
asterisk >= 19.0.0, < 20.9.3 < 19.0.0, 20.9.3
asterisk >= 21.0.0, < 21.4.3 < 21.0.0, 21.4.3