Mozilla Firefox 4.0/4.0.1/5.0 Browser Engine memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in Mozilla Firefox 4.0/4.0.1/5.0 (Web Browser). It has been declared as very critical. This vulnerability affects an unknown functionality of the component Browser Engine. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The browser engine in Mozilla Firefox 4.x through 5, SeaMonkey 2.x before 2.3, Thunderbird before 6, and possibly other products does not properly implement JavaScript, which allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unspecified vectors.

The weakness was presented 08/18/2011 by Rafael Gieschke (TippingPoint) with TippingPoint's Zero Day Initiative as Bug 655660 as not defined bug report (Bugzilla). The advisory is available at This vulnerability was named CVE-2011-2991. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 11/18/2021).

The vulnerability scanner Nessus provides a plugin with the ID 55878 (FreeBSD : mozilla -- multiple vulnerabilities (834591a9-c82f-11e0-897d-6c626dd55a41)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 165573 (SUSE Enterprise Linux Security Update Mozilla Firefox (SUSE-SA:2011:037)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at X-Force (69221) and Tenable (55878).







CPE 2.3info

CPE 2.2info


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

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

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Current Price Estimation: 🔍


Nessus ID: 55878
Nessus Name: FreeBSD : mozilla -- multiple vulnerabilities (834591a9-c82f-11e0-897d-6c626dd55a41)
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OpenVAS ID: 70261
OpenVAS Name: FreeBSD Ports: firefox
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: no mitigation known
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08/01/2011 🔍
08/16/2011 +15 days 🔍
08/16/2011 +0 days 🔍
08/17/2011 +1 days 🔍
08/18/2011 +1 days 🔍
08/18/2011 +0 days 🔍
03/23/2015 +1313 days 🔍
11/18/2021 +2432 days 🔍



Advisory: Bug 655660
Researcher: Rafael Gieschke (TippingPoint)
Organization: TippingPoint's Zero Day Initiative
Status: Not defined
Confirmation: 🔍

CVE: CVE-2011-2991 (🔍)

X-Force: 69221
Vulnerability Center: 32737 - Firefox <6, Thunderbird <6, SeaMonkey <2.3 Remote DoS and Code Execution Vulnerability due to Memory Corruption in The Browser Engine JavaScript Implementation, Critical
SecurityFocus: 49166 - RETIRED: Mozilla Firefox/Thunderbird/SeaMonkey MFSA 2011-29 through -30 Multiple Vulnerabilities
Secunia: 49055


Created: 03/23/2015 04:50 PM
Updated: 11/18/2021 07:05 AM
Changes: 03/23/2015 04:50 PM (63), 03/29/2017 06:24 PM (11), 11/18/2021 06:55 AM (4), 11/18/2021 07:05 AM (1)
Complete: 🔍
Cache ID: 3:DEA:40


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