Is CVE-2026-14534 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-14534 being exploited in the wild.

How severe is CVE-2026-14534?

High severity, with a CVSS score of 8.8, published 4 July 2026.

Which products and versions are affected?

fickling (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.11.

Is there a fix for CVE-2026-14534?

Yes. fickling (PyPI): upgrade to 0.1.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-14534 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-14534?

Check whether you run fickling (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-14534: Trail of Bits fickling sandbox bypass via incomplete denylist

CVE-2026-14534 · Severity: high · CVSS 8.8 · Published 2026-07-04

Fickling is a security tool used to analyze and safely load Python "pickle" files, which are often used in AI and machine learning models. A vulnerability in Fickling's safety scanner allowed malicious files to bypass security checks by using specific Python modules that were missing from its blocklist. If an attacker convinces a user to scan or load a specially crafted malicious file, they could execute arbitrary commands on the user's system, potentially leading to a full system takeover or data theft.

Technologies: fickling (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-14534 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-14534 being exploited in the wild.
How severe is CVE-2026-14534?: High severity, with a CVSS score of 8.8, published 4 July 2026.
Which products and versions are affected?: fickling (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.11.
Is there a fix for CVE-2026-14534?: Yes. fickling (PyPI): upgrade to 0.1.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-14534 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-14534?: Check whether you run fickling (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

fickling (PyPI): upgrade to 0.1.11 or later
```
pip install "fickling>=0.1.11"
```

Technical details

A deserialization vulnerability exists in Trail of Bits fickling (versions <= 0.1.10) due to an incomplete denylist in the `UNSAFE_IMPORTS` list within `fickle.py`. The `check_safety()` function fails to identify payloads utilizing `_posixsubprocess.fork_exec`, `site.execsitecustomize`, or `atexit._run_exitfuncs` as dangerous, returning a 'LIKELY_SAFE' verdict. Because `fickling.load()` uses this verdict as a security gate before calling `pickle.loads()`, an attacker can achieve arbitrary code execution via a crafted pickle file. The vulnerability is further exacerbated because the `UnusedVariables` heuristic is bypassed by the `SETITEMS` opcode pattern. This issue was addressed in version 0.1.11 by expanding the blocklist.

Affected products

Trail of Bits fickling <= 0.1.10

Identifiers

CVE-2026-14534
PYSEC-2026-2149

Timeline

2026-05-06: patched: Fix merged into master and version 0.1.11 released.
2026-07-04: disclosed: CVE-2026-14534 published.

References

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