CVE-2025-56005

high Red Hat
CVSS v3 Base Score
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score
0.9%
Exploitation probability in 30 days
Top 24% most likely to be exploited
Attack Characteristics
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Confidentiality
High
Integrity
High
Availability
High
Published: January 20, 2026 (115 days ago)
Last Modified: January 20, 2026
Vendor: Red Hat

Description

An undocumented and unsafe feature in the PLY (Python Lex-Yacc) library 3.11 allows Remote Code Execution (RCE) via the `picklefile` parameter in the `yacc()` function. This parameter accepts a `.pkl` file that is deserialized with `pickle.load()` without validation. Because `pickle` allows execution of embedded code via `__reduce__()`, an attacker can achieve code execution by passing a malicious pickle file. The parameter is not mentioned in official documentation or the GitHub repository, yet it is active in the PyPI version. This introduces a stealthy backdoor and persistence risk. NOTE: A third-party states that this vulnerability should be rejected because the proof of concept does not demonstrate arbitrary code execution and fails to complete successfully.

CWE

CWE-502

Affected Products

Fence Agents Remediation OperatorMigration Toolkit for ContainersMigration Toolkit for VirtualizationOpenShift Developer Tools and ServicesOpenShift PipelinesOpenShift Service Mesh 2OpenShift Service Mesh 3Red Hat Advanced Cluster Security 4Red Hat Ansible Automation Platform Ansible Core 2Red Hat Ceph Storage 7

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 github.com