---
title: "CVE-2015-6525\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-2015-6525?format=md
keywords: index, follow
---

# CVE-2015-6525

Publication date 24 August 2015

Last updated 24 July 2024

---

Ubuntu priority

**Medium**

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

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## Description

Multiple integer overflows in the evbuffer API in Libevent 2.0.x before
2.0.22 and 2.1.x before 2.1.5-beta allow context-dependent attackers to
cause a denial of service or possibly have other unspecified impact via
"insanely large inputs" to the (1) evbuffer\_add, (2) evbuffer\_prepend, (3)
evbuffer\_expand, (4) exbuffer\_reserve\_space, or (5) evbuffer\_read function,
which triggers a heap-based buffer overflow or an infinite loop. NOTE:
this identifier was SPLIT from CVE-2014-6272 per ADT3 due to different
affected versions.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2015-6525?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| libevent | 15.04 vivid | Not affected |
| 14.04 LTS trusty | Fixed 2.0.21-stable-1ubuntu1.14.04.1 |
| 12.04 LTS precise | Fixed 2.0.16-stable-1ubuntu0.1 |

---

* [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-2015-6525?format=md#patch-details)

## Notes

---

### [mdeslaur](https://launchpad.net/~mdeslaur)

CVE was split from CVE-2014-6272, but fixes were already applied
in usn-2477-1

### 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 |
| --- | --- |
| libevent | * Upstream:   [7b21c4e](https://github.com/libevent/libevent/commit/7b21c4eabf1f3946d3f63cce1319c490caab8ecf) * Upstream:   [20d6d44](https://github.com/libevent/libevent/commit/20d6d4458bee5d88bda1511c225c25b2d3198d6c) * Upstream:   [841ecbd](https://github.com/libevent/libevent/commit/841ecbd96105c84ac2e7c9594aeadbcc6fb38bc4) |

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-6525)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-6525)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-6525)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-6525)

### Other references

* <http://www.debian.org/security/2015/dsa-3119>
* <http://archives.seul.org/libevent/users/Jan-2015/msg00010.html>
* <https://www.cve.org/CVERecord?id=CVE-2015-6525>