{"id":"CVE-2026-45809","state":"PUBLISHED","title":"OpenSIPS: Denial of Service in watcherinfo XML generation from oversized watcher URI","description":"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.","publishedAt":"2026-08-04T23:30:03.111Z","updatedAt":"2026-08-05T13:57:39.468Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["OpenSIPS opensips"],"affected":[{"vendor":"OpenSIPS","product":"opensips","versions":[{"version":">= 3.4.0, < 3.6.6","status":"affected"},{"version":">= 4.0.0-beta, < 4.0.0-rc1","status":"affected"}]}],"references":["https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56","https://github.com/OpenSIPS/opensips/commit/c5970d3ee25b457ad2d78fe6e9662a12dae577cd","https://github.com/OpenSIPS/opensips/commit/dd86461b71ff4a4f5194205896ae5f48f144240d"],"weaknesses":["CWE-121"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/45xxx/CVE-2026-45809.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45809","state":"PUBLISHED","datePublished":"2026-08-04T23:30:03.111Z","dateUpdated":"2026-08-05T13:57:39.468Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-13T08:19:32.604Z"},"containers":{"cna":{"title":"OpenSIPS: Denial of Service in watcherinfo XML generation from oversized watcher URI","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"OpenSIPS","product":"opensips","versions":[{"version":">= 3.4.0, < 3.6.6","status":"affected"},{"version":">= 4.0.0-beta, < 4.0.0-rc1","status":"affected"}]}],"references":[{"url":"https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56","name":"https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/OpenSIPS/opensips/commit/c5970d3ee25b457ad2d78fe6e9662a12dae577cd","name":"https://github.com/OpenSIPS/opensips/commit/c5970d3ee25b457ad2d78fe6e9662a12dae577cd","tags":["x_refsource_MISC"]},{"url":"https://github.com/OpenSIPS/opensips/commit/dd86461b71ff4a4f5194205896ae5f48f144240d","name":"https://github.com/OpenSIPS/opensips/commit/dd86461b71ff4a4f5194205896ae5f48f144240d","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-121","lang":"en","description":"CWE-121: Stack-based Buffer Overflow","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-04T23:30:03.111Z"},"source":{"advisory":"GHSA-gx83-2gh8-7v56","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-05T13:57:30.647530Z","id":"CVE-2026-45809","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-05T13:57:39.468Z"}}]}}}