---
title: "CVE-2015-8394\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-2015-8394?format=md
keywords: index, follow
---

# CVE-2015-8394

Publication date 1 December 2015

Last updated 25 August 2025

---

Ubuntu priority

**Low**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2015-8394?format=md#impact-score)

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## Description

PCRE before 8.38 mishandles the (?(<digits>) and (?(R<digits>) conditions,
which allows remote attackers to cause a denial of service (integer
overflow) or possibly have unspecified other impact via a crafted regular
expression, as demonstrated by a JavaScript RegExp object encountered by
Konqueror.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2015-8394?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| pcre2 | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| pcre3 | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Fixed 2:8.35-7.1ubuntu1.3 |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Fixed 1:8.31-2ubuntu2.2 |
| 12.04 LTS precise | Fixed 8.12-4ubuntu0.2 |

---

* [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-2015-8394?format=md#patch-details)

## Notes

---

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

Issue affects PCRE3 only
Marking 'low' since it requires PCRE to operate on untrusted regular
expressions which is not very likely

---

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

0001-Add-missing-integer-overflow-checks.patch in jessie

### 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 |
| --- | --- |
| pcre3 | * Upstream:   <http://vcs.pcre.org/pcre?view=revision&revision=1589> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8394)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-8394)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-8394)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-8394)

### Related Ubuntu Security Notices (USN)

+ [USN-2943-1](https://usn.ubuntu.com/USN-2943-1)
+ PCRE vulnerabilities
+ 29 March 2016

### Other references

* <http://www.openwall.com/lists/oss-security/2015/11/29/1>
* <http://vcs.pcre.org/pcre/code/trunk/ChangeLog?view=markup>
* <https://www.cve.org/CVERecord?id=CVE-2015-8394>