Mozilla Firefox up to 38.x append memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as critical has been found in Mozilla Firefox up to 38.x (Web Browser). This affects the function ArrayBufferBuilder::append. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

The ArrayBufferBuilder::append function in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, and Thunderbird before 38.1 accesses unintended memory locations, which has unspecified impact and attack vectors.

The weakness was presented 07/06/2015 by Karthikeyan Bhargavan (Paul) with Mozilla Developers (Website). The advisory is shared at This vulnerability is uniquely identified as CVE-2015-2739 since 03/25/2015. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/23/2022).

The vulnerability scanner Nessus provides a plugin with the ID 84550 (CentOS 5 / 6 / 7 : firefox (CESA-2015:1207)), 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 123836 (CentOS Security Update for thunderbird (CESA-2015:1455)).

Upgrading to version 39.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at X-Force (104393) and Tenable (84550).







CPE 2.3info

CPE 2.2info


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VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 8.7

VulDB Base Score: 10.0
VulDB Temp Score: 8.7
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Class: Memory corruption
CWE: CWE-119

Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

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Nessus ID: 84550
Nessus Name: CentOS 5 / 6 / 7 : firefox (CESA-2015:1207)
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OpenVAS ID: 703300
OpenVAS Name: Debian Security Advisory DSA 3300-1 (iceweasel - security update)
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Threat Intelligenceinfo

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Recommended: Upgrade
Status: 🔍
Upgrade: Firefox 39.0


03/25/2015 🔍
07/02/2015 +99 days 🔍
07/02/2015 +0 days 🔍
07/05/2015 +3 days 🔍
07/05/2015 +0 days 🔍
07/06/2015 +1 days 🔍
07/06/2015 +0 days 🔍
05/23/2022 +2513 days 🔍



Advisory: RHSA-2015:1207
Researcher: Karthikeyan Bhargavan (Paul)
Organization: Mozilla Developers
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-2739 (🔍)

X-Force: 104393 - Mozilla Firefox and Thunderbird ArrayBufferBuilder::append code execution
SecurityTracker: 1032783
Vulnerability Center: 50991 - Mozilla Firefox, Firefox ESR and Thunderbird Remote Unspecified Vulnerability - CVE-2015-2739, Critical
SecurityFocus: 75541 - Mozilla Firefox/Thunderbird Multiple Security Vulnerabilities


Created: 07/06/2015 10:19 AM
Updated: 05/23/2022 01:33 PM
Changes: 07/06/2015 10:19 AM (65), 07/03/2017 09:01 AM (14), 05/23/2022 01:22 PM (3), 05/23/2022 01:28 PM (1), 05/23/2022 01:33 PM (2)
Complete: 🔍
Cache ID: 44:8F3:40


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