Severity by source
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
Network-delivered pickle with low complexity, no attacker auth, but requires victim to load the file (UI:R); full RCE yields C/I/A:H.
Primary rating from Vendor (VulnCheck).
CVSS VectorVendor: VulnCheck
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
Lifecycle Timeline
3DescriptionCVE.org
picklescan before 0.0.29 fails to detect malicious pickle files using idlelib.autocomplete.AutoComplete.fetch_completions in reduce methods. Attackers can embed undetected code in pickle files that executes arbitrary commands when loaded by victims.
AnalysisAI
Detection bypass in picklescan versions prior to 0.0.29 allows attackers to smuggle arbitrary code execution payloads through malicious pickle files by leveraging idlelib.autocomplete.AutoComplete.fetch_completions inside the __reduce__ method. Because the scanner does not flag this built-in Python function as dangerous, victims who rely on picklescan to vet PyTorch models or other pickle artifacts will load attacker-controlled code under pickle.load(). Publicly available exploit code exists (in the GHSA advisory), though no active in-the-wild exploitation has been reported.
Technical ContextAI
picklescan is a Python security utility (pip/picklescan) used to statically scan pickle files for dangerous opcodes and callables before deserialization, frequently applied to PyTorch model weights distributed via Hugging Face and similar registries. The root cause is a CWE-502 deserialization weakness manifesting as an incomplete denylist: the scanner's catalog of dangerous callables omits idlelib.autocomplete.AutoComplete.fetch_completions, a function in Python's standard library IDLE module that internally evaluates supplied expressions during tab-completion logic. By returning this callable from __reduce__, an attacker turns pickle deserialization into expression evaluation (e.g., __import__('os').system(...)) without tripping any of picklescan's detectors. The CPE cpe:2.3:a:picklescan:picklescan:*:*:* covers all versions before the 0.0.29 fix.
RemediationAI
Upgrade picklescan to 0.0.29 or later (pip install --upgrade 'picklescan>=0.0.29'), which incorporates the upstream fix in commit aecd11be98702caa9ba9b12189d91ad596a36114 referenced from the GHSA at https://github.com/mmaitre314/picklescan/security/advisories/GHSA-7cq8-mj8x-j263. If immediate upgrade is not feasible, treat picklescan output as advisory only and do not load untrusted pickle files based solely on a clean scan; preferred compensating controls include switching model distribution to safetensors where possible (eliminates pickle-based RCE entirely but requires re-saving models), executing pickle.load only inside a sandboxed/ephemeral process with no network or filesystem write access (adds operational overhead and may break model loaders that expect local cache), and explicitly blocking idlelib.* imports via a custom Unpickler.find_class allowlist (most reliable short-term mitigation but must be paired with a broader allowlist policy to be effective).
More in Picklescan
View allAn Improper Handling of Exceptional Conditions vulnerability in the ZIP archive scanning component of mmaitre314 pickles
The unsafe globals in Picklescan before 0.0.25 do not include ssl. Rated medium severity (CVSS 6.8), this vulnerability
picklescan before 0.0.21 does not treat 'pip' as an unsafe global. Rated medium severity (CVSS 5.3), this vulnerability
Remote code execution against users of picklescan versions prior to 1.0.4 is achievable by smuggling any blocked functio
Arbitrary code execution in picklescan versions prior to 1.0.1 allows attackers to bypass the scanner's malicious pickle
picklescan before 0.0.22 only considers standard pickle file extensions in the scope for its vulnerability scan. Rated m
Remote code execution in picklescan versions prior to 1.0.4 allows attackers to bypass the scanner's safety validation b
Arbitrary code execution bypass in picklescan before 1.0.4 allows attackers to smuggle malicious pickle files past the s
Detection bypass in picklescan versions prior to 0.0.27 allows attackers to smuggle malicious Python pickle files past t
Remote code execution in picklescan before 0.0.33 enables attackers to bypass the tool's malicious-pickle detection by s
Arbitrary file write in picklescan before 0.0.33 lets attackers bypass the tool's dangerous-call blocklist by abusing di
Arbitrary code execution in picklescan before 0.0.33 allows remote attackers to bypass the scanner's malicious-pickle de
Same weakness CWE-502 – Deserialization of Untrusted Data
View allSame technique Deserialization
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2025-210308
GHSA-gq8p-2329-gh3x