{"answers":{"affected":"4 open source packages ship an affected version, including mlflow. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4137 exists.","fix":"Upgrade mlflow to 3.11.0 or later.","what":"CVE-2026-4137 is a high-severity unsafe deserialization vulnerability in Lfprojects Mlflow, published on 18 May 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-4137 and fix it if it is affected.\n\nWhat it is: CVE-2026-4137 is a high-severity unsafe deserialization vulnerability in Lfprojects Mlflow, published on 18 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4137 exists.\n\nAffected packages and fixed versions:\n- mlflow (Bitnami): affected all versions; fixed in 3.11.0\n- mlflow (PyPI): affected all versions; fixed in 3.11.0\n- mlflow (PyPI): affected from 1.26.0; fixed in 3.11.0\n- mlflow (PyPI): affected from 1.26.0; fixed in 3.11.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-4137/ (Markdown: https://insights.sbomify.com/CVE-2026-4137/index.md)","id":"CVE-2026-4137","markdown":"https://insights.sbomify.com/CVE-2026-4137/index.md","name":"CVE-2026-4137","record":{"aliases":["BIT-mlflow-2026-4137","CLSA-2026-1780879898","GHSA-f2m9-wcf4-cwwx","PYSEC-2026-2655"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"MLflow library","requires_auth":"low_privilege","summary":"Local attackers can tamper with world-writable temporary model artifacts to achieve arbitrary code execution via unsafe deserialization in MLflow.","user_interaction":"not_required","vuln_class":"deserialization"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"@huntr_ai","cpe":[{"product":"mlflow","vendor":"lfprojects"}],"cvss":{"score":7,"severity":"high","source":"cna","vector":"CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.0"},"cwes":[{"id":"CWE-378","name":"Creation of Temporary File With Insecure Permissions"}],"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.","ecosystems":["Bitnami","PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Incomplete Fix for CVE-2025-10279: Insecure Temporary Directory Permissions in mlflow/mlflow","id":"CVE-2026-4137","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Bitnami","product":"lfprojects:mlflow","products":["lfprojects:mlflow"],"type":"deserialization","year":"2026"},"n_packages":4,"n_references":2,"next":{"headline":"DX Unanswered Comments \u003c= 1.7 - Cross-Site Request Forgery via Settings Update","id":"CVE-2026-4138"},"packages":[{"ecosystem":"Bitnami","fixed":["3.11.0"],"introduced":["0"],"last_affected":[],"package":"mlflow","purl":"pkg:bitnami/mlflow","source":"BIT-mlflow-2026-4137"},{"ecosystem":"PyPI","fixed":["3.11.0"],"introduced":["0"],"last_affected":[],"package":"mlflow","purl":"pkg:pypi/mlflow","source":"PYSEC-2026-2655"},{"ecosystem":"PyPI","fixed":["3.11.0"],"introduced":["1.26.0"],"last_affected":[],"package":"mlflow","purl":null,"source":"GHSA-f2m9-wcf4-cwwx"},{"ecosystem":"PyPI","fixed":["3.11.0"],"introduced":["1.26.0"],"last_affected":[],"package":"mlflow","purl":"pkg:pypi/mlflow","source":"GHSA-f2m9-wcf4-cwwx"}],"prev":{"headline":"Membership Plugin – Restrict Content \u003c= 3.2.24 - Unvalidated Redirect in Password Reset Flow via rcp_redirect","id":"CVE-2026-4136"},"products":["mlflow/mlflow"],"published":"2026-05-18","related":[{"cvss_score":9.3,"headline":"MLflow Server-Side Request Forgery","id":"CVE-2026-64849","kev_date_added":"2026-08-19","published":"2026-08-17"},{"cvss_score":10,"headline":"Command Injection in mlflow/mlflow","id":"CVE-2025-15379","kev_date_added":null,"published":"2026-03-30"},{"cvss_score":10,"headline":"Remote Code Execution due to Full Controlled File Write in mlflow/mlflow","id":"CVE-2024-0520","kev_date_added":null,"published":"2024-06-06"},{"cvss_score":10,"headline":"Path Traversal: '\\..\\filename'","id":"CVE-2023-6977","kev_date_added":null,"published":"2023-12-20"},{"cvss_score":10,"headline":"Improper Neutralization of Special Elements Used in a Template Engine in mlflow/mlflow","id":"CVE-2023-6709","kev_date_added":null,"published":"2023-12-12"},{"cvss_score":10,"headline":"MLflow Arbitrary File Upload","id":"CVE-2023-6015","kev_date_added":null,"published":"2023-11-16"},{"cvss_score":10,"headline":"MLflow Arbitrary File Write","id":"CVE-2023-6018","kev_date_added":null,"published":"2023-11-16"}],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"Bitnami","prefix":"BIT"},{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-05-19","vendors":["mlflow"]},"summary":"Local attackers can tamper with world-writable temporary model artifacts to achieve arbitrary code execution via unsafe deserialization in MLflow.","url":"https://insights.sbomify.com/CVE-2026-4137/"}