CVE-2026-22608: CWE-184: Incomplete List of Disallowed Inputs in trailofbits fickling
Fickling is a Python pickling decompiler and static analyzer. Prior to version 0.1.7, both ctypes and pydoc modules aren't explicitly blocked. Even other existing pickle scanning tools (like picklescan) do not block pydoc.locate. Chaining these two together can achieve RCE while the scanner still reports the file as LIKELY_SAFE. This issue has been patched in version 0.1.7.
AI Analysis
Technical Summary
CVE-2026-22608 affects the Python tool 'fickling', a pickling decompiler and static analyzer used to inspect Python pickled data. Prior to version 0.1.7, fickling's input validation was incomplete, specifically failing to block the use of the 'ctypes' and 'pydoc' modules. These modules can be leveraged to bypass security checks because 'pydoc.locate' can dynamically locate and execute arbitrary code, and 'ctypes' can be used to invoke low-level system calls. Attackers can chain these modules to craft malicious pickle payloads that achieve remote code execution (RCE) while the scanner incorrectly classifies the payload as likely safe. This vulnerability is rooted in CWE-184 (incomplete list of disallowed inputs) and CWE-502 (deserialization of untrusted data). The CVSS 4.0 base score is 8.9, indicating high severity, with attack vector network, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The flaw was patched in version 0.1.7 by explicitly blocking these modules. Although no known exploits are currently in the wild, the vulnerability poses a significant risk to environments using fickling for security analysis or reverse engineering of Python pickled data, especially in automated scanning pipelines that rely on fickling's safety assessments.
Potential Impact
For European organizations, the impact of CVE-2026-22608 can be substantial, particularly for those in sectors such as software development, cybersecurity, and incident response that utilize fickling for analyzing Python serialized data. Exploitation could lead to remote code execution on systems running vulnerable versions, potentially allowing attackers to execute arbitrary commands, steal sensitive data, disrupt services, or pivot within networks. This risk is heightened in environments where pickled data is received from untrusted sources or integrated into automated security workflows. The false negative detection (scanner reporting malicious files as likely safe) undermines trust in security tooling, increasing the likelihood of undetected compromise. Organizations relying on fickling in CI/CD pipelines or malware analysis may inadvertently expose themselves to attacks. While no active exploits are known, the ease of exploitation and high impact necessitate urgent remediation to prevent potential breaches.
Mitigation Recommendations
1. Upgrade fickling to version 0.1.7 or later immediately to ensure the patch blocking 'ctypes' and 'pydoc' modules is applied. 2. Supplement static analysis with dynamic runtime monitoring to detect suspicious deserialization activities or unexpected module usage, especially involving 'ctypes' or 'pydoc'. 3. Implement strict input validation and sanitization on all Python pickled data received from untrusted or external sources before analysis. 4. Employ network segmentation and least privilege principles to limit the impact of potential RCE on systems running fickling. 5. Regularly audit and review security tools and their update status within security operations to prevent use of outdated vulnerable versions. 6. Consider alternative or complementary pickle scanning tools that have robust blocking of dangerous modules and verify their detection capabilities against known evasion techniques. 7. Educate developers and security analysts about the risks of unsafe deserialization and the importance of using updated tools.
Affected Countries
Germany, France, United Kingdom, Netherlands, Sweden, Finland, Italy, Spain
CVE-2026-22608: CWE-184: Incomplete List of Disallowed Inputs in trailofbits fickling
Description
Fickling is a Python pickling decompiler and static analyzer. Prior to version 0.1.7, both ctypes and pydoc modules aren't explicitly blocked. Even other existing pickle scanning tools (like picklescan) do not block pydoc.locate. Chaining these two together can achieve RCE while the scanner still reports the file as LIKELY_SAFE. This issue has been patched in version 0.1.7.
AI-Powered Analysis
Technical Analysis
CVE-2026-22608 affects the Python tool 'fickling', a pickling decompiler and static analyzer used to inspect Python pickled data. Prior to version 0.1.7, fickling's input validation was incomplete, specifically failing to block the use of the 'ctypes' and 'pydoc' modules. These modules can be leveraged to bypass security checks because 'pydoc.locate' can dynamically locate and execute arbitrary code, and 'ctypes' can be used to invoke low-level system calls. Attackers can chain these modules to craft malicious pickle payloads that achieve remote code execution (RCE) while the scanner incorrectly classifies the payload as likely safe. This vulnerability is rooted in CWE-184 (incomplete list of disallowed inputs) and CWE-502 (deserialization of untrusted data). The CVSS 4.0 base score is 8.9, indicating high severity, with attack vector network, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The flaw was patched in version 0.1.7 by explicitly blocking these modules. Although no known exploits are currently in the wild, the vulnerability poses a significant risk to environments using fickling for security analysis or reverse engineering of Python pickled data, especially in automated scanning pipelines that rely on fickling's safety assessments.
Potential Impact
For European organizations, the impact of CVE-2026-22608 can be substantial, particularly for those in sectors such as software development, cybersecurity, and incident response that utilize fickling for analyzing Python serialized data. Exploitation could lead to remote code execution on systems running vulnerable versions, potentially allowing attackers to execute arbitrary commands, steal sensitive data, disrupt services, or pivot within networks. This risk is heightened in environments where pickled data is received from untrusted sources or integrated into automated security workflows. The false negative detection (scanner reporting malicious files as likely safe) undermines trust in security tooling, increasing the likelihood of undetected compromise. Organizations relying on fickling in CI/CD pipelines or malware analysis may inadvertently expose themselves to attacks. While no active exploits are known, the ease of exploitation and high impact necessitate urgent remediation to prevent potential breaches.
Mitigation Recommendations
1. Upgrade fickling to version 0.1.7 or later immediately to ensure the patch blocking 'ctypes' and 'pydoc' modules is applied. 2. Supplement static analysis with dynamic runtime monitoring to detect suspicious deserialization activities or unexpected module usage, especially involving 'ctypes' or 'pydoc'. 3. Implement strict input validation and sanitization on all Python pickled data received from untrusted or external sources before analysis. 4. Employ network segmentation and least privilege principles to limit the impact of potential RCE on systems running fickling. 5. Regularly audit and review security tools and their update status within security operations to prevent use of outdated vulnerable versions. 6. Consider alternative or complementary pickle scanning tools that have robust blocking of dangerous modules and verify their detection capabilities against known evasion techniques. 7. Educate developers and security analysts about the risks of unsafe deserialization and the importance of using updated tools.
Affected Countries
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-01-07T21:50:39.534Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6961b006ed32c7f018eb8ffd
Added to database: 1/10/2026, 1:48:54 AM
Last enriched: 1/17/2026, 7:44:14 AM
Last updated: 2/6/2026, 4:27:15 AM
Views: 97
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