{"id":"CVE-2026-72687","state":"PUBLISHED","title":"Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service","description":"A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier. Elasticsearch decodes and deserializes the identifier before confirming that it was legitimately issued by the cluster, and a size value carried inside the identifier drives an allocation that is neither capped nor accounted for by the available memory-usage controls. The resulting out-of-memory condition is fatal and terminates the affected node process, resulting in a denial of service.","publishedAt":"2026-08-13T19:11:00.432Z","updatedAt":"2026-08-13T20:34:33.600Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"elastic"},"assigner":"elastic","products":["Elastic Elasticsearch"],"affected":[{"vendor":"Elastic","product":"Elasticsearch","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThanOrEqual":"8.19.19","versionType":"semver"},{"version":"9.0.0","status":"affected","lessThanOrEqual":"9.4.4","versionType":"semver"},{"version":"9.5.0","status":"affected","versionType":"semver"}]}],"references":["https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-79/389506"],"weaknesses":["CWE-789"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72687.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72687","state":"PUBLISHED","datePublished":"2026-08-13T19:11:00.432Z","dateUpdated":"2026-08-13T20:34:33.600Z","assignerShortName":"elastic","assignerOrgId":"271b6943-45a9-4f3a-ab4e-976f3fa05b5a","dateReserved":"2026-08-10T11:17:58.731Z"},"containers":{"cna":{"title":"Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service","descriptions":[{"lang":"en","value":"A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier. Elasticsearch decodes and deserializes the identifier before confirming that it was legitimately issued by the cluster, and a size value carried inside the identifier drives an allocation that is neither capped nor accounted for by the available memory-usage controls. The resulting out-of-memory condition is fatal and terminates the affected node process, resulting in a denial of service."}],"affected":[{"vendor":"Elastic","product":"Elasticsearch","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThanOrEqual":"8.19.19","versionType":"semver"},{"version":"9.0.0","status":"affected","lessThanOrEqual":"9.4.4","versionType":"semver"},{"version":"9.5.0","status":"affected","versionType":"semver"}]}],"references":[{"url":"https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-79/389506"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":6.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-789","description":"CWE-789 Memory Allocation with Excessive Size Value","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"elastic","orgId":"271b6943-45a9-4f3a-ab4e-976f3fa05b5a","dateUpdated":"2026-08-13T19:11:00.432Z"},"source":{"discovery":"Elastic"},"x_generator":{"engine":"Elastic CVE Publisher 1.0.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-13T20:23:14.534132Z","id":"CVE-2026-72687","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-13T20:34:33.600Z"}}]}}}