Mozilla Firefox 42 JavaScript Variable Assignment code

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as problematic, was found in Mozilla Firefox 42 (Web Browser). Affected is some unknown processing of the component JavaScript Variable Assignment. The manipulation with an unknown input leads to a code vulnerability. CWE is classifying the issue as CWE-17. This is going to have an impact on availability.

The weakness was released 12/15/2015 by Cajus Pollmeier (musicDespiteEverything) as MFSA2015-135 as confirmed security advisory (Website). The advisory is available at This vulnerability is traded as CVE-2015-7204 since 09/16/2015. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. The advisory points out:

Security researcher Cajus Pollmeier reported that Firefox 41 was crashing during some Javascript variable assignments. The issue was caused by an implementation error with unboxed objects and property storing in the JavaScript engine. This error could result in a potentially exploitable crash when triggered by JavaScript content as well as leading to errors on some websites.

The vulnerability scanner Nessus provides a plugin with the ID 87385 (FreeBSD : mozilla -- multiple vulnerabilities (2c2d1c39-1396-459a-91f5-ca03ee7c64c6)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 168484 (OpenSuSE Security Update for seamonkey (openSUSE-SU-2016:0307-1)).

Upgrading to version 43 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (87385). Entries connected to this vulnerability are available at 79805, 79807, 79808 and 79810.






  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍



VulDB Base Score: 🔍
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Class: Code
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Current Price Estimation: 🔍


Nessus ID: 87385
Nessus Name: FreeBSD : mozilla -- multiple vulnerabilities (2c2d1c39-1396-459a-91f5-ca03ee7c64c6)
Nessus File: 🔍
Nessus Risk: 🔍
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Nessus Context: 🔍

OpenVAS ID: 803852
OpenVAS Name: Mozilla Firefox Multiple Vulnerabilities - Dec15 (Windows)
OpenVAS File: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

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Upgrade: Firefox 43


09/16/2015 🔍
12/15/2015 +90 days 🔍
12/15/2015 +0 days 🔍
12/15/2015 +0 days 🔍
12/15/2015 +0 days 🔍
12/16/2015 +1 days 🔍
12/16/2015 +0 days 🔍
12/16/2015 +0 days 🔍
12/16/2015 +0 days 🔍
07/01/2022 +2389 days 🔍



Advisory: MFSA2015-135
Researcher: Cajus Pollmeier (musicDespiteEverything)
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-7204 (🔍)
SecurityTracker: 1034426
Vulnerability Center: 55289 - Mozilla Firefox 41 - 42 Remote DoS in JavaScript Engine - CVE-2015-7204, High
SecurityFocus: 79280 - Mozilla Firefox Multiple Security Vulnerabilities

See also: 🔍


Created: 12/16/2015 11:16 AM
Updated: 07/01/2022 08:35 AM
Changes: 12/16/2015 11:16 AM (71), 05/15/2018 09:06 AM (11), 07/01/2022 08:35 AM (3)
Complete: 🔍


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