{"id":"CVE-2026-62365","title":"Wazuh: Heap Buffer Overflow in DecodeWinevt() join_data Accumulation via Crafted EventChannel XML","summary":"Wazuh is an open-source security platform providing unified XDR and SIEM protection for endpoints and cloud workloads. DecodeWinevt in src/analysisd/decoders/winevtchannel.c accumulates unnamed Windows EventChannel Data element contents …","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-122"],"vendor":"wazuh","product":"wazuh","affected":["wazuh >= 3.9.0, < 4.14.7"],"published":"2026-11-04","updated":"2026-11-04","sourceUpdated":"2026-11-04T22:46:40.298Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-62365","references":[{"url":"https://github.com/wazuh/wazuh/security/advisories/GHSA-whhr-gxxr-f6pm","label":"https://github.com/wazuh/wazuh/security/advisories/GHSA-whhr-gxxr-f6pm"},{"url":"https://github.com/wazuh/wazuh/pull/37198","label":"https://github.com/wazuh/wazuh/pull/37198"},{"url":"https://github.com/wazuh/wazuh/commit/07c5b2829f671eac0436412701a346a26555fdc7","label":"https://github.com/wazuh/wazuh/commit/07c5b2829f671eac0436412701a346a26555fdc7"},{"url":"https://github.com/wazuh/wazuh/releases/tag/v4.14.7","label":"https://github.com/wazuh/wazuh/releases/tag/v4.14.7"}],"tags":["cve.org"],"ingestedAt":"2026-11-05T21:36:00.663Z","epss":0.00284,"epssPercentile":0.21033,"slug":"CVE-2026-62365","body":"## Overview\n\nWazuh is an open-source security platform providing unified XDR and SIEM protection for endpoints and cloud workloads. DecodeWinevt in src/analysisd/decoders/winevtchannel.c accumulates unnamed Windows EventChannel Data element contents into the fixed 65,535-byte join_data heap buffer but passes the growing content length, rather than the OS_MAXSTR buffer capacity, as the snprintf size. An enrolled agent can submit an EventChannel message containing four maximum-sized unnamed Data elements, causing the fourth accumulation to write beyond join_data and corrupt adjacent heap metadata. The subsequent free of join_data2 causes the wazuh-analysisd process to terminate, stopping log ingestion for all agents handled by that manager. This vulnerability is fixed in 4.14.7.\n\n## Affected\n\n- `wazuh >= 3.9.0, < 4.14.7`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}