{"id":"CVE-2026-4137","state":"PUBLISHED","title":"Incomplete Fix for CVE-2025-10279: Insecure Temporary Directory Permissions in mlflow/mlflow","description":"In mlflow/mlflow versions prior to 3.11.0, the `get_or_create_nfs_tmp_dir()` function in `mlflow/utils/file_utils.py` creates temporary directories with world-writable permissions (0o777), and the `_create_model_downloading_tmp_dir()` function in `mlflow/pyfunc/__init__.py` creates directories with group-writable permissions (0o770). These insecure permissions allow local attackers to tamper with model artifacts, such as cloudpickle-serialized Python objects, and achieve arbitrary code execution when the tampered artifacts are deserialized via `cloudpickle.load()`. This vulnerability is particularly critical in environments with shared NFS mounts, such as Databricks, where NFS is enabled by default. The issue is a continuation of the vulnerability class addressed in CVE-2025-10279, which was only partially fixed.","publishedAt":"2026-05-18T20:26:23.104Z","updatedAt":"2026-05-19T12:47:53.221Z","severity":{"score":7,"label":"High","version":"3.0","vector":"CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"@huntr_ai"},"assigner":"@huntr_ai","products":["mlflow mlflow/mlflow"],"affected":[{"vendor":"mlflow","product":"mlflow/mlflow","versions":[{"version":"unspecified","status":"affected","lessThan":"3.11.0","versionType":"custom"}]}],"references":["https://huntr.com/bounties/648dc30b-76c7-4433-86b8-f43d926fd8d6","https://github.com/mlflow/mlflow/commit/1dcbb0c2fbd1f446c328830e601ca13a28219b8a"],"weaknesses":["CWE-378"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/4xxx/CVE-2026-4137.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-4137","state":"PUBLISHED","datePublished":"2026-05-18T20:26:23.104Z","dateUpdated":"2026-05-19T12:47:53.221Z","assignerShortName":"@huntr_ai","assignerOrgId":"c09c270a-b464-47c1-9133-acb35b22c19a","dateReserved":"2026-03-13T15:15:45.839Z"},"containers":{"cna":{"title":"Incomplete Fix for CVE-2025-10279: Insecure Temporary Directory Permissions in mlflow/mlflow","descriptions":[{"lang":"en","value":"In mlflow/mlflow versions prior to 3.11.0, the `get_or_create_nfs_tmp_dir()` function in `mlflow/utils/file_utils.py` creates temporary directories with world-writable permissions (0o777), and the `_create_model_downloading_tmp_dir()` function in `mlflow/pyfunc/__init__.py` creates directories with group-writable permissions (0o770). These insecure permissions allow local attackers to tamper with model artifacts, such as cloudpickle-serialized Python objects, and achieve arbitrary code execution when the tampered artifacts are deserialized via `cloudpickle.load()`. This vulnerability is particularly critical in environments with shared NFS mounts, such as Databricks, where NFS is enabled by default. The issue is a continuation of the vulnerability class addressed in CVE-2025-10279, which was only partially fixed."}],"affected":[{"vendor":"mlflow","product":"mlflow/mlflow","versions":[{"version":"unspecified","status":"affected","lessThan":"3.11.0","versionType":"custom"}]}],"references":[{"url":"https://huntr.com/bounties/648dc30b-76c7-4433-86b8-f43d926fd8d6"},{"url":"https://github.com/mlflow/mlflow/commit/1dcbb0c2fbd1f446c328830e601ca13a28219b8a"}],"metrics":[{"cvssV3_0":{"version":"3.0","attackComplexity":"HIGH","attackVector":"LOCAL","availabilityImpact":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-378","type":"CWE","lang":"en","description":"CWE-378 Creation of Temporary File With Insecure Permissions"}]}],"providerMetadata":{"shortName":"@huntr_ai","orgId":"c09c270a-b464-47c1-9133-acb35b22c19a","dateUpdated":"2026-05-18T20:26:23.104Z"},"source":{"advisory":"648dc30b-76c7-4433-86b8-f43d926fd8d6","discovery":"EXTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://huntr.com/bounties/648dc30b-76c7-4433-86b8-f43d926fd8d6","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-19T12:47:50.311629Z","id":"CVE-2026-4137","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-19T12:47:53.221Z"}}]}}}