The remote host is missing an update to the system as announced in the referenced advisory.

Update your system with the appropriate patches or software upgrades.

The following packages are affected: asterisk18 asterisk CVE-2011-4063 chan_sip.c in the SIP channel driver in Asterisk Open Source 1.8.x before 1.8.7.1 and 10.x before 10.0.0-rc1 does not properly initialize variables during request parsing, which allows remote authenticated users to cause a denial of service (daemon crash) via a malformed request.