Deserialization of Untrusted DataWeakness · CWE-502

CVE-2025-71376

HIGH · 8.1 CVSS v3.1 Published 2026-06-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
88/100
Remediation priority · High
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

picklescan before version 0.0.29 fails to detect malicious pickle files when attackers embed code using idlelib.autocomplete.AutoComplete.fetch_completions within reduce methods. This scanner bypass allows attackers to craft pickle files containing arbitrary code that executes when loaded by victim applications.

MitigationUpgrade picklescan to version 0.0.29 or later to resolve the detection gap. Until then, avoid loading untrusted pickle files from unknown sources regardless of scanner results.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check picklescan installed version
    Run `pip show picklescan` or `pip list | grep picklescan` to retrieve the installed version number
    Affected if Version is lower than 0.0.29 or version cannot be determined (package not installed)
  2. Verify pickle file scanning workflow
    Identify whether your application or CI/CD pipeline uses picklescan to validate pickle files from untrusted or external sources
    Affected if Picklescan is used as a security control to filter untrusted pickle files and the installed version is below 0.0.29
  3. Inspect pickle files for idlelib.autocomplete pattern
    Examine the raw bytes or disassemble suspicious pickle files using `pickle` module or `pickletools` to look for strings containing 'idlelib.autocomplete.AutoComplete.fetch_completions' within __reduce__ or __reduce_ex__ method definitions
    Affected if A pickle file intended for untrusted input contains the idlelib.autocomplete.AutoComplete.fetch_completions pattern within reduce methods

You are affected if picklescan version is below 0.0.29 AND you use picklescan to validate pickle files from untrusted sources.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade picklescan to version 0.0.29 or later to resolve the detection gap. Until then, avoid loading untrusted pickle files from unknown sources regardless of scanner results.

Recommended fix High confidence

picklescan 0.0.29

  1. Check the current version of picklescan installed (pip show picklescan or pip list)
  2. Upgrade to version 0.0.29 or later using pip install picklescan>=0.0.29
  3. Verify the upgrade was successful by running picklescan --version

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
25.0 hours of engineering $4,400
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-71376 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-71376 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data