CVE-2026-115886

MLflow: SSRF on unauthenticated MLflow servers via third-party scorer kwargs in the scorer invoke, register, and GenAI evaluate endpoints

Medium 6.5

MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. From 3.12.0rc0 until 3.17.0, the scorer invoke, register, and GenAI evaluate endpoints, including unauthenticated POST /ajax-api/3.0/mlflow/scorer/invoke, accept serialized third-party scorer data that Scorer.model_validate_json resolves using a module-path allowlist without constraining the selected class or its constructor arguments. When optional trulens and trulens-providers-litellm packages are installed, an attacker can select mlflow.genai.scorers.trulens, choose a model URI outside MLflow's native provider registry so execution uses the LiteLLM fallback, and supply api_base and api_key values that cause the server to send an outbound request to an attacker-chosen or internal host with attacker-controlled headers and body. The vulnerable deserialization occurs before a tracking-store lookup or job submission. This issue is fixed in version 3.17.0.

Assigner
GitHub_M
Published
2026-10-23
Updated
2026-10-23
Reserved
2026-10-23

Seen in other sources

Scores

SourceCVSSScoreSeverityVector
GitHub_M3.16.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Weaknesses

Affected

VendorProductVersions
mlflow mlflow >= 3.12.0rc0, < 3.17.0 (affected)

References

Full CVE JSON record (5.2)

API · GitHub · cve.org

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "mlflow",
          "vendor": "mlflow",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.12.0rc0, \u003c 3.17.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. From 3.12.0rc0 until 3.17.0, the scorer invoke, register, and GenAI evaluate endpoints, including unauthenticated POST /ajax-api/3.0/mlflow/scorer/invoke, accept serialized third-party scorer data that Scorer.model_validate_json resolves using a module-path allowlist without constraining the selected class or its constructor arguments. When optional trulens and trulens-providers-litellm packages are installed, an attacker can select mlflow.genai.scorers.trulens, choose a model URI outside MLflow\u0027s native provider registry so execution uses the LiteLLM fallback, and supply api_base and api_key values that cause the server to send an outbound request to an attacker-chosen or internal host with attacker-controlled headers and body. The vulnerable deserialization occurs before a tracking-store lookup or job submission. This issue is fixed in version 3.17.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-470",
              "description": "CWE-470: Use of Externally-Controlled Input to Select Classes or Code (\u0027Unsafe Reflection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-918",
              "description": "CWE-918: Server-Side Request Forgery (SSRF)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-23T21:17:21.462Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/mlflow/mlflow/security/advisories/GHSA-2wqp-q3c6-ccj5",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/mlflow/mlflow/security/advisories/GHSA-2wqp-q3c6-ccj5"
        },
        {
          "name": "https://github.com/mlflow/mlflow/pull/25890",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mlflow/mlflow/pull/25890"
        },
        {
          "name": "https://github.com/mlflow/mlflow/commit/bac30b4148c4f40045b4d4db07ae60ab3838803f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mlflow/mlflow/commit/bac30b4148c4f40045b4d4db07ae60ab3838803f"
        },
        {
          "name": "https://github.com/mlflow/mlflow/releases/tag/v3.17.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mlflow/mlflow/releases/tag/v3.17.0"
        }
      ],
      "source": {
        "advisory": "GHSA-2wqp-q3c6-ccj5",
        "discovery": "UNKNOWN"
      },
      "title": "MLflow: SSRF on unauthenticated MLflow servers via third-party scorer kwargs in the scorer invoke, register, and GenAI evaluate endpoints"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-115886",
    "datePublished": "2026-10-23T21:17:21.462Z",
    "dateReserved": "2026-10-23T19:37:27.176Z",
    "dateUpdated": "2026-10-23T21:17:21.462Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}