# CVE-2026-53873: picklescan incomplete blocklist bypass in profile module

Source: https://junglewise.ai/threats/cve-2026-53873-picklescan-incomplete-blocklist-bypass-in-profile-module  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-20  
License: CC BY 4.0 with a link back

CVE-2026-53873 · Severity: critical · CVSS 9.8 · Published 2026-06-17

picklescan is a security tool used to scan Python pickle files for malicious code. A flaw in its protection mechanism allows specially crafted files to bypass security checks and execute unauthorized commands on the system. This could lead to a complete system takeover or data theft while the tool incorrectly reports that the file is safe.

Technologies: [picklescan (PyPI)](https://junglewise.ai/threats/technologies/picklescan). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-53873 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-53873 being exploited in the wild.

**How severe is CVE-2026-53873?** Critical severity, with a CVSS score of 9.8, published 17 June 2026.

**Which products and versions are affected?** picklescan (PyPI) < 1.0.4, ECOSYSTEM:introduced=0,fixed=1.0.4.

**Is there a fix for CVE-2026-53873?** Yes. picklescan (PyPI): upgrade to 1.0.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-53873 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-53873?** Check whether you run picklescan (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

- picklescan (PyPI): upgrade to 1.0.4 or later

  ```sh
  pip install "picklescan>=1.0.4"
  ```


## Technical details

picklescan versions prior to 1.0.4 suffer from an incomplete blocklist (CWE-184) regarding the Python 'profile' module. While the scanner attempted to block 'Profile.run' and 'Profile.runctx', it failed to account for the module-level 'profile.run()' and 'profile.runctx()' functions due to exact string matching logic in the opcode parser. An attacker can craft a malicious pickle file that calls these module-level functions to execute arbitrary Python code via the internal 'exec()' call. Because the scanner fails to flag these specific entry points, it reports zero security issues for a payload that results in Remote Code Execution (RCE). The issue is resolved in version 1.0.4 by expanding the blocklist.

## Affected products

- picklescan picklescan < 1.0.4

## Identifiers

- CVE-2026-53873
- GHSA-7wx9-6375-f5wh
- PYSEC-2026-455

## Timeline

- 2026-03-02: advisory: GitHub Security Advisory GHSA-7wx9-6375-f5wh published
- 2026-06-17: disclosed: CVE-2026-53873 published to NVD

## References

- [https://github.com/mmaitre314/picklescan/security/advisories/GHSA-7wx9-6375-f5wh](https://github.com/mmaitre314/picklescan/security/advisories/GHSA-7wx9-6375-f5wh)
- [https://www.vulncheck.com/advisories/picklescan-arbitrary-code-execution-via-profile-run-blocklist-bypass](https://www.vulncheck.com/advisories/picklescan-arbitrary-code-execution-via-profile-run-blocklist-bypass)

## Related threats

- [picklescan detection bypass via _operator.methodcaller](https://junglewise.ai/threats/cve-2025-71375-picklescan-detection-bypass-via-operator-methodcaller)
- [picklescan security bypass via operator.methodcaller](https://junglewise.ai/threats/cve-2025-71373-picklescan-security-bypass-via-operator-methodcaller)
- [Picklescan detection bypass via numpy getlincoef gadget](https://junglewise.ai/threats/cve-2025-71372-picklescan-detection-bypass-via-numpy-getlincoef-gadget)
- [picklescan safety check bypass via PyTorch decoder basichandlers](https://junglewise.ai/threats/cve-2025-71369-picklescan-safety-check-bypass-via-pytorch-decoder-basichandlers)
- [picklescan security bypass via _operator.attrgetter function call](https://junglewise.ai/threats/cve-2025-71367-picklescan-security-bypass-via-operator-attrgetter-function-call)