---
id: CVE-2015-7764
aliases:
  - GHSA-chg9-3c3p-ch23
  - PYSEC-2017-50
title: Lemur uses static IV per key
summary: Lemur uses static IV per key
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
vendor: lemur
product: lemur
ecosystem: pip
affected:
  - lemur < 0.1.5
patched:
  - lemur 0.1.5
published: '2022-05-13'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:49:22.227010371Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-chg9-3c3p-ch23'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2015-7764'
  - url: 'https://github.com/Netflix/lemur/issues/117'
  - url: 'https://github.com/kvesteri/sqlalchemy-utils/issues/166'
  - url: >-
      https://github.com/Netflix/lemur/commit/394e18f76e5eb534d95160945ebc231ec3b4c794
  - url: 'https://github.com/Netflix/lemur'
  - url: >-
      https://github.com/pypa/advisory-database/tree/main/vulns/lemur/PYSEC-2017-50.yaml
  - url: 'http://www.openwall.com/lists/oss-security/2015/10/20/3'
tags:
  - osv
  - pip
epss: 0.01511
epssPercentile: 0.72916
ingestedAt: '2026-09-12T03:13:01.688Z'
---

## Overview

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

## Affected packages

- `lemur < 0.1.5`

## Remediation

Upgrade to a patched release:

- `lemur 0.1.5`