CVE-2025-71371 picklescan CVE debrief

Who should care

Defenders responsible for systems using picklescan, particularly those loading untrusted pickle files, should assess exposure and prioritize verification and remediation. This includes operators, security teams, and vulnerability management teams. They should verify picklescan version, restrict loading untrusted pickle files, and monitor for suspicious activity.

Why it matters

CVE-2025-71371 is a high-severity vulnerability in picklescan that allows for arbitrary code execution due to a detection bypass. Defenders should prioritize verifying and upgrading picklescan, restricting untrusted pickle file loads, and monitoring for suspicious activity.

• Potential for arbitrary code execution when loading untrusted pickle files
• Bypass of picklescan detection for malicious pickle files
• Need for verification of picklescan version and remediation to prevent exploitation
• Possible impact on systems loading untrusted pickle files, requiring defensive monitoring and controls

Technical summary

The picklescan library before version 0.0.29 fails to detect malicious pickle files due to the use of code.InteractiveInterpreter.runcode in reduce methods. This allows attackers to craft pickle payloads that bypass picklescan detection and execute arbitrary code when loaded via pickle.load(). The vulnerability allows for arbitrary code execution when loading untrusted pickle files and bypasses picklescan detection for malicious pickle files. Defenders should prioritize verifying and upgrading to picklescan version 0.0.29 or later.

Defensive priority

Defenders should prioritize verifying and upgrading to picklescan version 0.0.29 or later, and restrict loading untrusted pickle files.

Recommended defensive actions

• Verify picklescan version and upgrade to 0.0.29 or later
• Restrict loading untrusted pickle files
• Monitor for suspicious pickle file loads
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability in picklescan before version 0.0.29, which fails to detect malicious pickle files, allowing for arbitrary code execution. Evidence is limited to public CVE and NVD records. Defenders should verify picklescan version and restrict loading untrusted pickle files. The vulnerability allows for arbitrary code execution when loading untrusted pickle files and bypasses picklescan detection for malicious pickle files.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.