{"id":"CVE-2026-62365","aliases":["EUVD-2026-117190","GHSA-whhr-gxxr-f6pm"],"status":"published","title":"Wazuh: Heap Buffer Overflow in DecodeWinevt() join_data Accumulation via Crafted EventChannel XML","description":"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 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.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00284,"percentile":0.21063,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-122"],"published":"2026-11-04T22:46:40Z","modified":"2026-11-05T13:04:46Z","products":[{"vendor":"wazuh","product":"wazuh"}],"references":[{"url":"https://github.com/wazuh/wazuh/security/advisories/GHSA-whhr-gxxr-f6pm","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/wazuh/wazuh/pull/37198","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/wazuh/wazuh/commit/07c5b2829f671eac0436412701a346a26555fdc7","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/wazuh/wazuh/releases/tag/v4.14.7","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62365.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-62365","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-62365","title":"Wazuh: Heap Buffer Overflow in DecodeWinevt() join_data Accumulation via Crafted EventChannel XML","description":"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 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.","status":"published","published":"2026-11-04T22:46:40.298Z","modified":"2026-11-04T22:46:40.298Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-122"],"updated_at":"2026-11-04T23:40:09.798467Z"}],"euvd":[{"id":"EUVD-2026-117190","description":"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 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.","status":"published","published":"2026-11-04T22:46:40Z","modified":"2026-11-04T22:46:40Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-05T00:47:41.139684Z"}],"nvd":[{"id":"CVE-2026-62365","description":"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 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.","status":"published","published":"2026-11-04T23:17:56.583Z","modified":"2026-11-06T21:29:48.8Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-122"],"updated_at":"2026-11-07T00:02:36.119898Z"}],"osv":[{"id":"CVE-2026-62365","title":"Wazuh: Heap Buffer Overflow in DecodeWinevt() join_data Accumulation via Crafted EventChannel XML","description":"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 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.","status":"published","published":"2026-11-04T22:46:40.298Z","modified":"2026-11-08T07:14:02.748037324Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-122"],"updated_at":"2026-11-08T03:29:52.421856Z"}]}}