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.
https://github.com/wazuh/wazuh/security/advisories/GHSA-whhr-gxxr-f6pm
https://github.com/wazuh/wazuh/releases/tag/v4.14.7
https://github.com/wazuh/wazuh/pull/37198
https://github.com/wazuh/wazuh/commit/07c5b2829f671eac0436412701a346a26555fdc7