# CVE-2015-7764: PYSEC-2017-50 - Lemur 0.1.4 does not use sufficient entropy in its IV when encrypting AES in CBC mode.

Source: https://junglewise.ai/threats/cve-2015-7764-lemur-uses-static-iv-per-key  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2017-08-09  
License: CC BY 4.0 with a link back

CVE-2015-7764 · Severity: low · CVSS 3.1 · Published 2017-08-09

Lemur 0.1.4 does not use sufficient entropy in its IV when encrypting AES in CBC mode.

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

## Quick answers

**Is CVE-2015-7764 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2015-7764 being exploited in the wild.

**How severe is CVE-2015-7764?** Low severity, with a CVSS score of 3.1, published 9 August 2017.

**Which products and versions are affected?** lemur (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.5, ECOSYSTEM:introduced=0,fixed=0.2.1.

**Is there a fix for CVE-2015-7764?** Yes. lemur (PyPI): upgrade to 0.1.5, 0.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2015-7764?** Check whether you run lemur (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

- lemur (PyPI): upgrade to 0.1.5, 0.2.1 or later

  ```sh
  pip install "lemur>=0.2.1"
  ```


## Affected products

- lemur (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.5, ECOSYSTEM:introduced=0,fixed=0.2.1

## Identifiers

- CVE-2015-7764
- GHSA-chg9-3c3p-ch23
- PYSEC-2017-50

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