{"id":"CVE-2026-26204","summary":"Wazuh: Heap-based NULL WRITE Buffer Underflow in GetAlertData","details":"Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 1.0.0 to before version 4.14.4, a heap-based out-of-bounds WRITE occurs in GetAlertData, resulting in writing a NULL byte exactly 1 byte before the start of the buffer allocated by strdup. Due to unsigned integer underflow and pointer arithmetic wrapping, the write lands at offset -1 from the buffer, corrupting heap metadata. A malicious actor can potentially leverage this issue through a compromised agent to cause denial of service or heap corruption by injecting a specially crafted alert into the alerts log file monitored by wazuh-logcollector. This issue has been patched in version 4.14.4.","aliases":["GHSA-j4c7-hwjw-8857"],"modified":"2026-07-08T08:12:44.658650866Z","published":"2026-04-29T17:43:44.911Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26204.json","cwe_ids":["CWE-124","CWE-191"],"cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/wazuh/wazuh/releases/tag/v4.14.4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26204.json"},{"type":"ADVISORY","url":"https://github.com/wazuh/wazuh/security/advisories/GHSA-j4c7-hwjw-8857"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-26204"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/wazuh/wazuh","events":[{"introduced":"0"},{"fixed":"5933ec9ebee76fb2546e5f7fc9f3a27d0aeca605"}],"database_specific":{"extracted_events":[{"introduced":"1.0.0"},{"fixed":"4.14.4"}],"source":["AFFECTED_FIELD","CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:wazuh:wazuh:*:*:*:*:*:*:*:*"}}],"versions":["v4.14.4-rc1","coverity-w10-4.14.4","coverity-w9-4.14.4","v4.14.1","v4.14.3-rc1","v3.13.1","v3.13.0","v3.12.0","v3.8.0","v3.7.0","v3.6.1","v3.6.0","v3.5.0","v3.2.0","v3.1.0","v2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-26204.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H"}]}