{"id":"CVE-2023-5632","summary":"Unconditionally adding an event to the epoll causes excessive CPU consumption","details":"In Eclipse Mosquito before and including 2.0.5, establishing a connection to the mosquitto server without sending data causes the EPOLLOUT event to be added, which results excessive CPU consumption. This could be used by a malicious actor to perform denial of service type attack. This issue is fixed in 2.0.6\n\n\n","modified":"2026-08-19T15:33:26.971116Z","published":"2023-10-18T08:34:34.788Z","database_specific":{"cna_assigner":"eclipse","cwe_ids":["CWE-834"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/5xxx/CVE-2023-5632.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/5xxx/CVE-2023-5632.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-5632"},{"type":"FIX","url":"https://github.com/eclipse/mosquitto/commit/18bad1ff32435e523d7507e9b2ce0010124a8f2d"},{"type":"FIX","url":"https://github.com/eclipse/mosquitto/pull/2053"},{"type":"PACKAGE","url":"https://github.com/eclipse/mosquitto"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse-mosquitto/mosquitto","events":[{"introduced":"c55424e8979c1fbc4a0a893f61f5b8f7e217f49d"},{"fixed":"18bad1ff32435e523d7507e9b2ce0010124a8f2d"}],"database_specific":{"cpe":"cpe:2.3:a:eclipse:mosquitto:2.0.5:*:*:*:*:*:*:*","extracted_events":[{"introduced":"2.0.5"},{"last_affected":"2.0.5"}],"source":["CPE_STRING","REFERENCES"]}}],"versions":["2.0.5","v2.0.5"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2023-5632.json","vanir_signatures_modified":"2026-08-19T15:33:26Z","vanir_signatures":[{"signature_type":"Line","signature_version":"v1","source":"https://github.com/eclipse-mosquitto/mosquitto/commit/18bad1ff32435e523d7507e9b2ce0010124a8f2d","target":{"file":"lib/packet_mosq.c"},"deprecated":false,"digest":{"threshold":0.9,"line_hashes":["339340532613465271204693980858278238153","136292289744382020139876670180840970972","21869194843853891625861881781520145664","285141719073239596503475120037193743720"]},"id":"CVE-2023-5632-2ab895b3"},{"deprecated":false,"digest":{"function_hash":"68487489615421562917012134159900078294","length":3121},"id":"CVE-2023-5632-580bb959","signature_type":"Function","signature_version":"v1","source":"https://github.com/eclipse-mosquitto/mosquitto/commit/18bad1ff32435e523d7507e9b2ce0010124a8f2d","target":{"file":"lib/packet_mosq.c","function":"packet__write"}}]}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}