---
title: "CVE-2016-1902\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2016-1902?format=md
keywords: index, follow
---

# CVE-2016-1902

Publication date 1 June 2016

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2016-1902?format=md#impact-score)

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## Description

The nextBytes function in the SecureRandom class in Symfony before 2.3.37,
2.6.x before 2.6.13, and 2.7.x before 2.7.9 does not properly generate
random numbers when used with PHP 5.x without the paragonie/random\_compat
library and the openssl\_random\_pseudo\_bytes function fails, which makes it
easier for attackers to defeat cryptographic protection mechanisms via
unspecified vectors.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| symfony | 16.04 LTS xenial | Not affected |
| 15.10 wily | Ignored end of life |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2016-1902?format=md#patch-details)

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| symfony | * Upstream:   <https://github.com/symfony/symfony/pull/17359> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | None |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1902)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-1902)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-1902)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-1902)

### Other references

* <http://symfony.com/blog/cve-2016-1902-securerandom-s-fallback-not-secure-when-openssl-fails>
* <https://github.com/symfony/symfony/pull/17359>
* <https://www.cve.org/CVERecord?id=CVE-2016-1902>