CVE-2026-14535
Description
A flaw was found in the fickling library, versions up to and including 0.1.11. A logic error in the security analysis passes allows an attacker to bypass intended safety checks during pickle deserialization. This vulnerability enables the invocation of arbitrary standard library modules, leading to the execution of malicious code. The fickling.load() API, designed as a security gate, incorrectly reports payloads as safe, allowing them to be deserialized and executed.
Statement
A flaw was found in Trail of Bits fickling versions through 0.1.11, where a logic error in the security analysis pipeline silently disables the MLAllowlist safety check. The UnsafeImportsML pass inadvertently populates the shared reported_shortened_code set for all imports, causing the MLAllowlist pass to skip its allowlist evaluation entirely. This allows standard library modules outside the denylist to pass check_safety() as LIKELY_SAFE, enabling arbitrary code execution when fickling.load() proceeds with deserialization. The upstream advisory rates this as Moderate severity; Red Hat's assessment reflects the arbitrary code execution impact in the CVSS score.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.8 | 9.8 | 8.8 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | Required | None | Required |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
