FKIE_CVE-2026-42276

Vulnerability from fkie_nvd - Published: 2026-05-08 05:16 - Updated: 2026-06-17 10:47
Severity
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Summary
Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the POST /chat/stop-chat-session/{chat_session_id} endpoint lets any authenticated user stop any other user's active chat session. The endpoint checks authentication but never verifies the session belongs to the caller. An attacker who knows a chat session UUID can kill another user's LLM generation mid-stream. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6.
References
security-advisories@github.comhttps://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8wExploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8wExploit, Vendor Advisory
Impacted products
Vendor Product Version
onyx onyx *
onyx onyx *
onyx onyx *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "onyx",
          "vendor": "onyx-dot-app",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.0.9"
            },
            {
              "status": "affected",
              "version": "\u003e= 3.1.0, \u003c 3.1.6"
            },
            {
              "status": "affected",
              "version": "\u003e= 3.2.0, \u003c 3.2.6"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:onyx:onyx:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8EA5C508-9DEA-44FA-A188-0B1B87FEDBDE",
              "versionEndExcluding": "3.0.9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:onyx:onyx:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "ABCC8200-5559-45DD-87E8-1CAD6E7D6828",
              "versionEndExcluding": "3.1.6",
              "versionStartIncluding": "3.1.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:onyx:onyx:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F4E43C7B-9888-4225-86E0-0309E34186D2",
              "versionEndExcluding": "3.2.6",
              "versionStartIncluding": "3.2.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the POST /chat/stop-chat-session/{chat_session_id} endpoint lets any authenticated user stop any other user\u0027s active chat session. The endpoint checks authentication but never verifies the session belongs to the caller. An attacker who knows a chat session UUID can kill another user\u0027s LLM generation mid-stream. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6."
    }
  ],
  "id": "CVE-2026-42276",
  "lastModified": "2026-06-17T10:47:37.107",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-42276",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-08T12:56:45.370877Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-08T05:16:10.557",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-rw6w-hp62-gc8w"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-639"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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