{"id":"CVE-2026-44253","state":"PUBLISHED","title":"Wazuh: Cluster Protocol Memory Exhaustion (DoS) via unbounded receive_str allocation and div_msg_box accumulation","description":"Wazuh is a free and open source platform used for threat prevention, detection, and response. From 3.9.0 until 4.14.5 and 5.0.0-beta2, the Wazuh cluster protocol in framework/wazuh/core/cluster/common.py allows an authenticated cluster node to exhaust memory on the master. The receive_str() method accepts an attacker-controlled total for InBuffer without a maximum, so a new_str command can request a multi-gigabyte bytearray and repeated requests accumulate in in_str. The divided-message path also retains flag_divided fragments under unique counters in div_msg_box without a count, aggregate-size, or expiration limit. Exploitation can disrupt agent connectivity and alert processing across the monitored environment. This issue is fixed in versions 4.14.5 and 5.0.0-beta2.","publishedAt":"2026-08-19T16:06:06.158Z","updatedAt":"2026-08-25T02:13:49.793Z","severity":{"score":4.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["wazuh wazuh"],"affected":[{"vendor":"wazuh","product":"wazuh","versions":[{"version":">= 3.9.0, < 4.14.5","status":"affected"},{"version":">= 5.0.0-beta1, < 5.0.0-beta2","status":"affected"}]}],"references":["https://github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2","https://github.com/wazuh/wazuh/pull/35173","https://github.com/wazuh/wazuh/commit/d29c5c89a0e16477545ca27f4e06229021e3183c","https://github.com/wazuh/wazuh/releases/tag/v4.14.5"],"weaknesses":["CWE-789","CWE-770"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/44xxx/CVE-2026-44253.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44253","state":"PUBLISHED","datePublished":"2026-08-19T16:06:06.158Z","dateUpdated":"2026-08-25T02:13:49.793Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-05T16:33:55.844Z"},"containers":{"cna":{"title":"Wazuh: Cluster Protocol Memory Exhaustion (DoS) via unbounded receive_str allocation and div_msg_box accumulation","descriptions":[{"lang":"en","value":"Wazuh is a free and open source platform used for threat prevention, detection, and response. From 3.9.0 until 4.14.5 and 5.0.0-beta2, the Wazuh cluster protocol in framework/wazuh/core/cluster/common.py allows an authenticated cluster node to exhaust memory on the master. The receive_str() method accepts an attacker-controlled total for InBuffer without a maximum, so a new_str command can request a multi-gigabyte bytearray and repeated requests accumulate in in_str. The divided-message path also retains flag_divided fragments under unique counters in div_msg_box without a count, aggregate-size, or expiration limit. Exploitation can disrupt agent connectivity and alert processing across the monitored environment. This issue is fixed in versions 4.14.5 and 5.0.0-beta2."}],"affected":[{"vendor":"wazuh","product":"wazuh","versions":[{"version":">= 3.9.0, < 4.14.5","status":"affected"},{"version":">= 5.0.0-beta1, < 5.0.0-beta2","status":"affected"}]}],"references":[{"url":"https://github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2","name":"https://github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/wazuh/wazuh/pull/35173","name":"https://github.com/wazuh/wazuh/pull/35173","tags":["x_refsource_MISC"]},{"url":"https://github.com/wazuh/wazuh/commit/d29c5c89a0e16477545ca27f4e06229021e3183c","name":"https://github.com/wazuh/wazuh/commit/d29c5c89a0e16477545ca27f4e06229021e3183c","tags":["x_refsource_MISC"]},{"url":"https://github.com/wazuh/wazuh/releases/tag/v4.14.5","name":"https://github.com/wazuh/wazuh/releases/tag/v4.14.5","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":4.9,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-789","lang":"en","description":"CWE-789: Memory Allocation with Excessive Size Value","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-19T16:06:06.158Z"},"source":{"advisory":"GHSA-h5r8-gvhv-cmp2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-25T02:13:22.111115Z","id":"CVE-2026-44253","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-25T02:13:49.793Z"}}]}}}