# CVE-2018-1000807: PyOpenSSL Use-After-Free vulnerability

Source: https://junglewise.ai/threats/cve-2018-1000807-pyopenssl-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2018-10-08  
License: CC BY 4.0 with a link back

CVE-2018-1000807 · Severity: low · CVSS 3.1 · Published 2018-10-08

Python Cryptographic Authority pyopenssl version prior to version 17.5.0 contains a CWE-416: Use After Free vulnerability in X509 object handling that can result in Use after free can lead to possible denial of service or remote code execution.. This attack appear to be exploitable via Depends on the calling application and if it retains a reference to the memory.. This vulnerability appears to have been fixed in 17.5.0.

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

## Quick answers

**Is CVE-2018-1000807 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-1000807 being exploited in the wild.

**How severe is CVE-2018-1000807?** Low severity, with a CVSS score of 3.1, published 8 October 2018.

**Which products and versions are affected?** pyopenssl (PyPI) ECOSYSTEM:introduced=0,fixed=17.5.0.

**Is there a fix for CVE-2018-1000807?** Yes. pyopenssl (PyPI): upgrade to 17.5.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2018-1000807?** Check whether you run pyopenssl (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

- pyopenssl (PyPI): upgrade to 17.5.0 or later

  ```sh
  pip install "pyopenssl>=17.5.0"
  ```


## Affected products

- pyopenssl (PyPI) ECOSYSTEM:introduced=0,fixed=17.5.0

## Identifiers

- CVE-2018-1000807
- GHSA-p28m-34f6-967q
- PYSEC-2018-23

## Related threats

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- [pyOpenSSL incorrect memory management in PKCS #12 handling](https://junglewise.ai/threats/cve-2018-1000808-pyopenssl-incorrect-memory-management-in-pkcs-12-handling)
- [PyOpenSSL Mishandles NUL Byte In Certificate Subject Alternative Name](https://junglewise.ai/threats/cve-2013-4314-pyopenssl-mishandles-nul-byte-in-certificate-subject-alternative)