{"id":"CVE-2026-63140","title":"Reachable Assertion (CWE-617) in Elasticsearch can lead to denial of service via Input Data Manipulation (CAPEC-153)","summary":"Reachable Assertion (CWE-617) in Elasticsearch can lead to denial of service via Input Data Manipulation (CAPEC-153). A specially crafted search request containing a null value in a specific query clause causes an internal assertion to b…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-617"],"vendor":"elastic","product":"elasticsearch","affected":["elasticsearch >= 8.0.0, < 8.19.19","elasticsearch >= 9.0.0, < 9.3.8","elasticsearch >= 9.4.0, < 9.4.4"],"patched":["elasticsearch 9.4.4"],"published":"2026-07-21","updated":"2026-08-07","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-63140","references":[{"url":"https://discuss.elastic.co/t/elasticsearch-8-19-19-9-3-8-9-4-4-security-update-esa-2026-64/388565","label":"security@elastic.co"}],"tags":["nvd"],"epss":0.0024,"epssPercentile":0.15398,"ingestedAt":"2026-08-07T23:18:01.329Z","slug":"CVE-2026-63140","body":"## Overview\n\nReachable Assertion (CWE-617) in Elasticsearch can lead to denial of service via Input Data Manipulation (CAPEC-153). A specially crafted search request containing a null value in a specific query clause causes an internal assertion to be raised during query parsing. Because Elasticsearch treats assertion failures as fatal errors, this terminates the affected node process. A low-privileged authenticated user with read access to at least one index can exploit this condition with a single request to cause a node to terminate, disrupting search availability. In a single-node deployment this fully stops Elasticsearch; in a multi-node cluster it reduces cluster capacity for each affected node.\n\n## Affected\n\n- `elasticsearch >= 8.0.0, < 8.19.19`\n- `elasticsearch >= 9.0.0, < 9.3.8`\n- `elasticsearch >= 9.4.0, < 9.4.4`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `elasticsearch 9.4.4`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}