Vulnerability-Lookup

CVE-2026-59279 (GCVE-0-2026-59279)

Vulnerability from cvelistv5 – Published: 2026-08-21 12:07 – Updated: 2026-08-21 14:28

Title

Unbounded persistent session allocation via repeated initialize requests

Summary

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 versions: Spring AI: 2.0.0

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-21 14:28 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

vmware CNA under the mitre root

CNA scorecard C 64/100 over 247 records in the last 180 days details

References

1 reference

URL	Tags
https://spring.io/security/cve-2026-59279

Impacted products

1 product

Vendor	Product	Version	CPE status
Spring	Spring AI	Affected: 2.0.0 (custom)	guessed

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-59279

Vulnerability from fkie_nvd - Published: 2026-08-21 12:16 - Updated: 2026-10-16 15:10

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	security@vmware.com	https://spring.io/security/cve-2026-59279	Vendor Advisory

Impacted products

	Vendor	Product	Version
	vmware	spring_ai	*

JSON

To clipboard

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    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Spring AI",
          "vendor": "Spring",
          "versions": [
            {
              "status": "affected",
              "version": "2.0.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@vmware.com"
    }
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    },
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GHSA-2G9X-R8W8-QJFF

Vulnerability from github – Published: 2026-08-21 12:30 – Updated: 2026-08-21 12:30

Details

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

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  ],
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    "github_reviewed": false,
    "github_reviewed_at": null,
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  },
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  "id": "GHSA-2g9x-r8w8-qjff",
  "modified": "2026-08-21T12:30:33Z",
  "published": "2026-08-21T12:30:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59279"
    },
    {
      "type": "WEB",
      "url": "https://spring.io/security/cve-2026-59279"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-59279 (GCVE-0-2026-59279)

FKIE_CVE-2026-59279

GHSA-2G9X-R8W8-QJFF

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour