{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-59279", "assignerOrgId": "dcf2e128-44bd-42ed-91e8-88f912c1401d", "state": "PUBLISHED", "assignerShortName": "vmware", "dateReserved": "2026-07-04T18:13:26.297Z", "datePublished": "2026-08-21T12:07:05.567Z", "dateUpdated": "2026-08-21T12:07:05.567Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "dcf2e128-44bd-42ed-91e8-88f912c1401d", "shortName": "vmware", "dateUpdated": "2026-08-21T12:07:05.567Z"}, "title": "Unbounded persistent session allocation via repeated initialize requests", "problemTypes": [{"descriptions": [{"lang": "en", "description": "Allocation of Resources Without Limits or Throttling", "type": "CWE", "cweId": "CWE-770"}]}], "impacts": [{"descriptions": [{"lang": "en", "value": "The MCP Streamable HTTP server transport (WebFlux and WebMvc variants) does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over time, gradually exhausting available memory and ultimately causing a Denial of Service that affects all legitimate clients."}]}], "affected": [{"vendor": "Spring", "product": "Spring AI", "versions": [{"status": "affected", "version": "2.0.0", "versionType": "custom"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "The MCP Streamable HTTP server transport (WebFlux and WebMvc variants) does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over time, gradually exhausting available memory and ultimately causing a Denial of Service that affects all legitimate clients.\nAffected versions:\nSpring AI: 2.0.0", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>The MCP Streamable HTTP server transport (WebFlux and WebMvc variants) does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over time, gradually exhausting available memory and ultimately causing a Denial of Service that affects all legitimate clients.</p><p>Affected versions:</p><ul><li>Spring AI: 2.0.0</li></ul>"}]}], "references": [{"url": "https://spring.io/security/cve-2026-59279"}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}}], "source": {"discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Spring AI", "vendor": "Spring", "versions": [{"status": "affected", "version": "2.0.0", "versionType": "custom"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "The MCP Streamable HTTP server transport (WebFlux and WebMvc variants) does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over time, gradually exhausting available memory and ultimately causing a Denial of Service that affects all legitimate clients.\nAffected versions:\nSpring AI: 2.0.0"}], "id": "CVE-2026-59279", "lastModified": "2026-08-21T12:16:30.013", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-08-21T12:16:30.013", "references": [{"source": "[email protected]", "url": "https://spring.io/security/cve-2026-59279"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-770"}], "source": "[email protected]", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2.0.0"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Spring AI", "source": "cna", "vendor": "Spring"}, "product": "spring_ai", "vendor": "spring"}], "created": "2026-08-21T13:30:04.234352+00:00", "updated": "2026-08-21T13:30:04.476995+00:00", "vendors": ["spring", "spring$PRODUCT$spring_ai"]}