{"id":"UBUNTU-CVE-2026-45809","details":"OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Versions prior to 3.6.6 and 4.0.0-rc1 contain a denial of service vulnerability in the watcherinfo generation functionality. An attacker can create an oversized watcher entry by sending a SUBSCRIBE Event: presence request with a long From URI, and then trigger presence.winfo watcherinfo XML generation for the same presentity. OpenSIPS copies the stored watcher URI into a fixed-size stack buffer, overflowing it and crashing the process. A remote attacker can crash an OpenSIPS worker in deployments that expose handle_subscribe() and allow watcherinfo (presence.winfo) generation. The issue is configuration-dependent because the presence and presence_xml modules must be loaded and SUBSCRIBE routing must be reachable. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.","modified":"2026-08-06T03:09:02.070049927Z","published":"2026-08-05T00:17:00Z","upstream":["CVE-2026-45809"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-45809"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-45809"},{"type":"REPORT","url":"https://github.com/OpenSIPS/opensips/commit/c5970d3ee25b457ad2d78fe6e9662a12dae577cd"},{"type":"REPORT","url":"https://github.com/OpenSIPS/opensips/commit/dd86461b71ff4a4f5194205896ae5f48f144240d"},{"type":"REPORT","url":"https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56"}],"affected":[{"package":{"name":"opensips","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/opensips?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.2-3build2","2.2.2-3build3","2.2.2-3build4"],"ecosystem_specific":{"binaries":[{"binary_version":"2.2.2-3build4","binary_name":"opensips"},{"binary_name":"opensips-b2bua-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-berkeley-bin","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-berkeley-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-carrierroute-module"},{"binary_name":"opensips-compression-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-console","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-cpl-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-dbhttp-module"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-dialplan-module"},{"binary_name":"opensips-emergency-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-geoip-module"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-http-modules"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-identity-module"},{"binary_name":"opensips-jabber-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-json-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-ldap-modules"},{"binary_name":"opensips-lua-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-memcached-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-mysql-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-perl-modules","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-postgres-module"},{"binary_name":"opensips-presence-modules","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-rabbitmq-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-radius-modules","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-redis-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-regex-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-restclient-module"},{"binary_name":"opensips-sctp-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-snmpstats-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-sqlite-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-tls-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-tlsmgm-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-unixodbc-module","binary_version":"2.2.2-3build4"},{"binary_name":"opensips-wss-module","binary_version":"2.2.2-3build4"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-xmlrpc-module"},{"binary_version":"2.2.2-3build4","binary_name":"opensips-xmpp-module"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45809.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}