Mozilla Firefox prior 2.0 8 Javascript Engine js_StringReplaceHelper memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as critical, has been found in Mozilla Firefox (Web Browser). Affected by this issue is the function js_StringReplaceHelper of the component Javascript Engine. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Multiple unspecified vulnerabilities in the JavaScript engine in Mozilla Firefox before 3.0.14 and 3.5.x before 3.5.2, Thunderbird before, and SeaMonkey before 1.1.19 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via vectors related to use of mutable strings in the js_StringReplaceHelper function in js/src/jsstr.cpp, and unknown vectors.

The weakness was disclosed 09/10/2009 by Juan Pablo Lopez Yacubian (TippingPoint) with TippingPoint's Zero Day Initiative as Bug 505305 as not defined bug report (Bugzilla). The advisory is shared for download at This vulnerability is handled as CVE-2009-3075. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details as well as a public exploit are known.

The exploit is available at It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 40932 (CentOS 4 / 5 : firefox / seamonkey (CESA-2009:1430)), 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 119088 (Red Hat Update for Xulrunner Firefox (RHSA-2009:1430)).

Upgrading to version 2.0 8 eliminates this vulnerability. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 11658.

The vulnerability is also documented in the databases at X-Force (53158), Tenable (40932), SecurityFocus (BID 36343†) and Vulnerability Center (SBV-23468†).







CPE 2.3info

CPE 2.2info


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VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.0

VulDB Base Score: 10.0
VulDB Temp Score: 9.0
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Class: Memory corruption
CWE: CWE-119

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

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Nessus ID: 40932
Nessus Name: CentOS 4 / 5 : firefox / seamonkey (CESA-2009:1430)
Nessus File: 🔍
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OpenVAS ID: 64870
OpenVAS Name: Debian Security Advisory DSA 1885-1 (xulrunner)
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 2.0 8
TippingPoint: 🔍

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09/04/2009 🔍
09/09/2009 +5 days 🔍
09/10/2009 +1 days 🔍
09/10/2009 +0 days 🔍
09/10/2009 +0 days 🔍
09/13/2009 +3 days 🔍
03/18/2015 +2012 days 🔍
08/22/2021 +2349 days 🔍



Advisory: Bug 505305
Researcher: Juan Pablo Lopez Yacubian (TippingPoint)
Organization: TippingPoint's Zero Day Initiative
Status: Not defined
Confirmation: 🔍

CVE: CVE-2009-3075 (🔍)

X-Force: 53158
SecurityFocus: 36343 - Mozilla Firefox MFSA 2009-47, -48, -49, -50, -51 Multiple Vulnerabilities
Vulnerability Center: 23468 - Mozilla Firefox <3.0.14 and 3.5-3.5.1 JavaScript Engine Multiple Unspecified Vulnerabilities, Medium

scip Labs:


Created: 03/18/2015 03:15 PM
Updated: 08/22/2021 11:54 AM
Changes: 03/18/2015 03:15 PM (69), 02/14/2017 04:30 PM (16), 08/22/2021 11:48 AM (3), 08/22/2021 11:54 AM (1)
Complete: 🔍
Cache ID: 44:14B:40


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