# PYSEC-2019-63 - The urllib3 library before 1.24.2 for Python mishandles certain cases where the desired set of CA…

Source: https://junglewise.ai/threats/pysec-2019-63-the-urllib3-library-before-1-24-2-for-python-mishandles-2035a86a  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2019-04-18  
License: CC BY 4.0 with a link back

Severity: info · Published 2019-04-18

The urllib3 library before 1.24.2 for Python mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to use of the ssl_context, ca_certs, or ca_certs_dir argument.

Technologies: [urllib3 (PyPI)](https://junglewise.ai/threats/technologies/urllib3). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 18 April 2019.

**Which products and versions are affected?** urllib3 (PyPI) ECOSYSTEM:introduced=0,fixed=1.24.2.

**Is there a fix for This vulnerability?** Yes. urllib3 (PyPI): upgrade to 1.24.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run urllib3 (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

- urllib3 (PyPI): upgrade to 1.24.2 or later

  ```sh
  pip install "urllib3>=1.24.2"
  ```


## Affected products

- urllib3 (PyPI) ECOSYSTEM:introduced=0,fixed=1.24.2

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