Vulnerability-Lookup

FKIE_CVE-2026-40968

Vulnerability from fkie_nvd - Published: 2026-04-28 15:16 - Updated: 2026-06-17 10:45

Severity

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

Summary

When an authenticated user is denied access to a gRPC method, their authenticated identity remains bound to the gRPC worker thread and can be inherited by a subsequent unauthenticated request on the same thread. This may allow the subsequent user to gain escalated permissions. Affected versions: Spring gRPC: 1.0.0 - 1.0.2 (fixed in 1.0.3). Older, unsupported versions are also affected.

References

	URL	Tags
	security@vmware.com	https://spring.io/security/cve-2026-40968	Vendor Advisory

Impacted products

	Vendor	Product	Version
	vmware	spring_grpc	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Spring gRPC",
          "vendor": "Spring",
          "versions": [
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              "status": "affected",
              "version": "1.0.0",
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            }
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      ],
      "source": "security@vmware.com"
    }
  ],
  "configurations": [
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              "versionEndExcluding": "1.0.3",
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    }
  ],
  "id": "CVE-2026-40968",
  "lastModified": "2026-06-17T10:45:57.280",
  "metrics": {
    "cvssMetricV31": [
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        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
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          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N",
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        "type": "Secondary"
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        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
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    "ssvcV203": [
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  "references": [
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    }
  ],
  "sourceIdentifier": "security@vmware.com",
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        {
          "lang": "en",
          "value": "CWE-653"
        }
      ],
      "source": "security@vmware.com",
      "type": "Secondary"
    }
  ]
}

CVE-2026-40968 (GCVE-0-2026-40968)

Vulnerability from cvelistv5 – Published: 2026-04-28 13:42 – Updated: 2026-04-28 14:36

Title

Spring gRPC SecurityContext leaks across requests on authorization failure

Summary

Severity

4.3 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-28 14:36 UTC

CWE

CWE-653 - Improper Isolation or Compartmentalization

Assigner

vmware mitre root

References

1 reference

URL	Tags
https://spring.io/security/cve-2026-40968

Impacted products

1 product

Vendor	Product	Version
Spring	Spring gRPC	Affected: 1.0.0 , < 1.0.3 (custom)

Show details on NVD website

JSON

To clipboard

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        "metrics": [
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                "id": "CVE-2026-40968",
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      "metrics": [
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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.

Detection rules are retrieved from Rulezet.

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.