high CVSS 7.8 EPSS 0.55%

CVE-2026-22609·Python vulnerability

Fickling is a Python pickling decompiler and static analyzer. Prior to version 0.1.7, the unsafe_imports() method in Fickling's static analyzer fails to flag several high-risk Python modules that can be used for arbitrary code execution. Malicious pickles importing these modules will not be detected as unsafe, allowing attackers to bypass Fickling's primary static safety checks. This issue has been patched in version 0.1.7.

Severity
high
Software
Python
Fixed in
0.1.7
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.55% — higher than 43% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-22609 scores 7.8 on CVSS, so a successful attack would be serious — but at 0.55%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

Until: 0.1.7

Fixed in: 0.1.7

How to fix this CVE

Update Fickling to version 0.1.7 or later to restore proper detection of high-risk Python modules in pickle files. The vulnerable versions allow attackers to craft malicious pickles that bypass static safety analysis by importing dangerous modules without triggering security warnings. Ensure your Python environment and all pickle-processing dependencies are updated to prevent unauthorized code execution.

sudo dnf update python3-fickling

Defensia detects this vulnerability

How to check if you are affected

  1. Check Fickling version: python3 -c "import fickling; print(fickling.__version__)" and verify it is 0.1.7 or later
  2. Identify if Fickling is used in your environment: grep -r "from fickling" /path/to/your/code or pip list | grep fickling
  3. Review pickle processing logs for failed static analysis checks or unexpected module imports: grep -i 'unsafe\|import' /var/log/application.log
  4. Run a test pickle through Fickling's analyzer to confirm unsafe_imports() correctly flags dangerous modules: python3 -c "from fickling.pickle import Pickle; p = Pickle.load(open('test.pkl', 'rb')); print(p.unsafe_imports)"

FAQ

What is CVE-2026-22609?

This vulnerability affects Fickling's static analyzer, which failed to recognize several dangerous Python modules used for code execution. Attackers could craft malicious pickle files that import these undetected modules, bypassing Fickling's safety checks and potentially executing arbitrary code.

Is CVE-2026-22609 being actively exploited?

No, CVE-2026-22609 is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are currently available.

What versions of Fickling are affected by CVE-2026-22609?

All versions of Fickling prior to 0.1.7 are affected. Version 0.1.7 and later include fixes for unsafe_imports() detection.

How do I check if my server is vulnerable to CVE-2026-22609?

Run: python3 -c "import fickling; print(fickling.__version__)" If the version is below 0.1.7, your installation is vulnerable.

Does Defensia detect CVE-2026-22609?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Fickling is installed on a monitored server, CVE-2026-22609 will appear in your dashboard with remediation steps.

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References

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