# CVE-2026-56304: picklescan - Arbitrary File Creation via logging.FileHandler Deserialization

> Unauthenticated attackers can create arbitrary files via unsafe pickle deserialization in picklescan, potentially causing denial of service.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 20 Jun 2026
- **Updated:** 24 Jun 2026
- **Also known as:** GHSA-hqgf-f82p-fjh7, GHSA-m7j5-r2p5-c39r, PYSEC-2026-225

## What is CVE-2026-56304?

CVE-2026-56304 is a medium-severity unsafe deserialization vulnerability in picklescan, published on 20 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

picklescan before 1.0.1 contains an unsafe pickle deserialization vulnerability allowing unauthenticated attackers to create arbitrary zero-byte files via logging.FileHandler class instantiation. Attackers can exploit this by crafting malicious pickle payloads to bypass RCE blocklists and create lock files or other filesystem artifacts, potentially causing denial of service or application disruption.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-56304?

3 open source packages ship an affected version, including picklescan. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `picklescan` | PyPI | All versions | 1.0.1 |
| `picklescan` | PyPI | All versions | 1.0.1 |
| `picklescan` | PyPI | All versions | 1.0.1 |

Products: Mmaitre314 Picklescan.

## How do I fix CVE-2026-56304?

Upgrade picklescan to 1.0.1 or later.

## Is CVE-2026-56304 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56304 exists.

## Other vulnerabilities in picklescan

- [CVE-2025-10155](https://insights.sbomify.com/CVE-2025-10155/): PickleScan Security Bypass Using Misleading File Extension (critical 9.3)
- [CVE-2025-10156](https://insights.sbomify.com/CVE-2025-10156/): PickleScan Security Bypass via Bad CRC in ZIP Archive (critical 9.3)
- [CVE-2025-10157](https://insights.sbomify.com/CVE-2025-10157/): PickleScan Bypasses Unsafe Globals Check Using Submodule Imports (critical 9.3)
- [CVE-2025-71348](https://insights.sbomify.com/CVE-2025-71348/): picklescan - Arbitrary Code Execution via torch.utils._config_module.load_config Bypass (high 7.6)
- [CVE-2025-71357](https://insights.sbomify.com/CVE-2025-71357/): picklescan - Arbitrary Code Execution via Undetected idlelib.pyshell.ModifiedInterpreter.runcommand (high 7.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-56304 and fix it if it is affected.

What it is: CVE-2026-56304 is a medium-severity unsafe deserialization vulnerability in picklescan, published on 20 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56304 exists.

Affected packages and fixed versions:
- picklescan (PyPI): affected all versions; fixed in 1.0.1
- picklescan (PyPI): affected all versions; fixed in 1.0.1
- picklescan (PyPI): affected all versions; fixed in 1.0.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-56304/ (Markdown: https://insights.sbomify.com/CVE-2026-56304/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-56304
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-56304
- OSV: https://osv.dev/vulnerability/CVE-2026-56304

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-56304/
Summaries are generated and may contain mistakes; the official description above is the record.