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CVE-2026-59822

Full vulnerability record from the local CVENow database.

Description

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid LiteLLM key. This issue is fixed in version 1.84.0.

Severity
HIGH
CVSS score
8.8 (v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-08 20:16:57.683000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
  "id": "CVE-2026-59822",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-08T20:16:57.683",
  "lastModified": "2026-10-25T17:10:00.197",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid LiteLLM key. This issue is fixed in version 1.84.0."
    },
    {
      "lang": "es",
      "value": "LiteLLM es un servidor proxy (AI Gateway) para llamar a las API de LLM en formato OpenAI (o nativo). Antes de la versión 1.84.0, el endpoint HTTP MCP Streamable de LiteLLM permitía a un atacante no autenticado utilizar un encabezado de autorización falsificado para activar una ruta de respaldo de paso de OAuth2 que reemplazaba la validación fallida de la clave de LiteLLM con un objeto UserAPIKeyAuth() vacío, permitiendo que las solicitudes llegaran a las herramientas de MCP sin una clave de LiteLLM válida. Este problema está solucionado en la versión 1.84.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "BerriAI",
          "product": "litellm",
          "versions": [
            {
              "version": "< 1.84.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/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",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "LOW",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
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        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
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          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-09-02T00:00:00+00:00",
          "id": "CVE-2026-59822",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
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          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "cisaExploitAdd": "2026-09-02",
  "cisaActionDue": "2026-09-16",
  "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "cisaVulnerabilityName": "BerriAI LiteLLM Improper Authentication Vulnerability",
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
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          "value": "CWE-287"
        },
        {
          "lang": "en",
          "value": "CWE-306"
        }
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    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:litellm:litellm:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "1.84.0",
              "matchCriteriaId": "0432AF82-95FD-4358-9414-7B41889CEFD2"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/BerriAI/litellm/commit/73869f0faf7d11ee21adcb5f91b8c33a340b6c2c",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/BerriAI/litellm/pull/26463",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking",
        "Patch"
      ]
    },
    {
      "url": "https://github.com/BerriAI/litellm/releases/tag/v1.84.0",
      "source": "[email protected]",
      "tags": [
        "Product",
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95q",
      "source": "[email protected]",
      "tags": [
        "Mitigation",
        "Patch",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-59822",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "US Government Resource"
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    },
    {
      "url": "https://www.wiz.io/blog/ai-infrastructure-honeypot",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Third Party Advisory"
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}