Mozilla Firefox up to 50 DOM Event use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k0.00

A vulnerability was found in Mozilla Firefox up to 50 (Web Browser). It has been rated as critical. Affected by this issue is an unknown code of the component DOM Event Handler. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Use-after-free while manipulating DOM events and removing audio elements due to errors in the handling of node adoption. This vulnerability affects Firefox < 50.1, Firefox ESR < 45.6, and Thunderbird < 45.6.

The weakness was published 12/13/2016 by Marcin Ressel as MFSA 2016-94 as confirmed security advisory (Website). The advisory is available at mozilla.org. This vulnerability is handled as CVE-2016-9899. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are unknown but a public exploit is available.

A public exploit has been developed by Marcin Ressel in HTML/Javascript and been published 2 months after the advisory. The exploit is available at exploit-db.com. It is declared as functional. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 900006 (CentOS 5 / 6 / 7 : firefox (CESA-2016:2946)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CentOS Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 236208 (Red Hat Update Firefox Security (RHSA-2016:2946)).

Upgrading to version 50.1 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (900006) and Exploit-DB (41042). Similar entries are available at 94489, 94491, 94492 and 94493.

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CPE 2.3info

CPE 2.2info

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CVSSv4info

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CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.8

VulDB Base Score: 6.3
VulDB Temp Score: 5.9
VulDB Vector: 🔍
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NVD Base Score: 9.8
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CVSSv2info

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Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Functional
Author: Marcin Ressel
Programming Language: 🔍
Download: 🔍

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Nessus ID: 900006
Nessus Name: CentOS 5 / 6 / 7 : firefox (CESA-2016:2946)
Nessus File: 🔍
Nessus Family: 🔍

OpenVAS ID: 881932
OpenVAS Name: CentOS Update for thunderbird CESA-2016:2973 centos7
OpenVAS File: 🔍
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Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Upgrade
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Upgrade: Firefox 50.1

Timelineinfo

12/07/2016 🔍
12/13/2016 +6 days 🔍
12/13/2016 +0 days 🔍
12/15/2016 +2 days 🔍
01/13/2017 +29 days 🔍
01/13/2017 +0 days 🔍
06/11/2018 +513 days 🔍
10/08/2022 +1580 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: MFSA 2016-94
Researcher: Marcin Ressel
Status: Confirmed

CVE: CVE-2016-9899 (🔍)
OVAL: 🔍

SecurityTracker: 1037461
SecurityFocus: 94885

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 12/15/2016 10:45
Updated: 10/08/2022 16:05
Changes: 12/15/2016 10:45 (54), 07/15/2017 16:52 (22), 10/08/2022 15:59 (3), 10/08/2022 16:05 (11)
Complete: 🔍

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