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GHSA-5QVF-77W7-X85R

Vulnerability from github – Published: 2026-09-16 12:30 – Updated: 2026-09-16 12:30

Details

As a result, an unauthenticated remote attacker may be able to craft a forged JWT that is incorrectly accepted as valid, leading to authentication bypass and potential compromise of confidentiality, integrity, and availability.

Severity

7.7 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-14916"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-241"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-16T11:16:40Z",
    "severity": "HIGH"
  },
  "details": "A JWT signature verification vulnerability affects Kong components that perform JWT validation for MCP OAuth2 or DataKit integrations inside Kong API Gateway Enterprise. The affected code does not properly validate that the JWT signing algorithm is compatible with the type of key used for verification.\n\n\n\nAs a result, an unauthenticated remote attacker may be able to craft a forged JWT that is incorrectly accepted as valid, leading to authentication bypass and potential compromise of confidentiality, integrity, and availability.",
  "id": "GHSA-5qvf-77w7-x85r",
  "modified": "2026-09-16T12:30:34Z",
  "published": "2026-09-16T12:30:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-14916"
    },
    {
      "type": "WEB",
      "url": "https://developer.konghq.com/gateway/changelog"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-14916 (GCVE-0-2026-14916)

Vulnerability from cvelistv5 – Published: 2026-09-16 10:11 – Updated: 2026-09-16 13:26

Title

Kong API Gateway Enterprise: JWT Algorithm-Confusion

Summary

A JWT signature verification vulnerability affects Kong components that perform JWT validation for MCP OAuth2 or DataKit integrations inside Kong API Gateway Enterprise. The affected code does not properly validate that the JWT signing algorithm is compatible with the type of key used for verification. As a result, an unauthenticated remote attacker may be able to craft a forged JWT that is incorrectly accepted as valid, leading to authentication bypass and potential compromise of confidentiality, integrity, and availability.

Severity

7.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-16 13:26 UTC

CWE

CWE-241 - Improper handling of unexpected data type

Assigner

Kong mitre root

References

1 reference

URL	Tags
https://developer.konghq.com/gateway/changelog/	release-notes

Impacted products

1 product

Vendor	Product	Version
Kong	Kong Enteprise Gateway	Affected: 3.15.0.0 , < 3.15.0.3 (custom) Affected: 3.14.0.0 , < 3.14.0.12 (custom) Affected: 3.13.0.0 , < 3.13.0.9 (custom) Affected: 3.12.0.0 , < 3.12.0.10 (custom) Affected: 3.10.0.0 , < 3.10.0.17 (custom) Affected: 3.4.0.0 , < 3.4.3.29 (custom)

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                  },
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                "timestamp": "2026-09-16T13:26:38.214554Z",
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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.

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.
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GHSA-5QVF-77W7-X85R

CVE-2026-14916 (GCVE-0-2026-14916)

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