Mozilla Firefox up to 52 Focus use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Mozilla Firefox up to 52. This affects an unknown function of the component Focus Handler. The manipulation leads to use after free. This vulnerability is referenced as CVE-2017-5434. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 52 (Web Browser). It has been rated as problematic. This issue affects some unknown processing of the component Focus 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 availability. The summary by CVE is:

A use-after-free vulnerability occurs when redirecting focus handling which results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

The bug was discovered 04/19/2017. The weakness was published 04/19/2017 by Huzaifa Sidhpurwala with Zero Day Initiative as MFSA 2017-10 as confirmed security advisory (Website). It is possible to read the advisory at mozilla.org. The identification of this vulnerability is CVE-2017-5434 since 01/13/2017. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 100687 (EulerOS 2.0 SP1 : firefox (EulerOS-SA-2017-1092)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Huawei Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276572 (Fedora Security Update for firefox (FEDORA-2017-31c64a0bbf)).

Upgrading to version 53 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 (100687), SecurityFocus (BID 97940†) and SecurityTracker (ID 1038320†). Similar entries are available at VDB-100289, VDB-100290, VDB-100291 and VDB-100292. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 6.9

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 100687
Nessus Name: EulerOS 2.0 SP1 : firefox (EulerOS-SA-2017-1092)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 881932
OpenVAS Name: CentOS Update for thunderbird CESA-2017:1201 centos7
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Firefox 53

Timelineinfo

01/13/2017 🔍
04/19/2017 +96 days 🔍
04/19/2017 +0 days 🔍
04/19/2017 +0 days 🔍
04/19/2017 +0 days 🔍
04/20/2017 +1 days 🔍
04/20/2017 +0 days 🔍
06/09/2017 +50 days 🔍
06/11/2018 +366 days 🔍
11/26/2025 +2725 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: MFSA 2017-10
Researcher: Huzaifa Sidhpurwala
Organization: Zero Day Initiative
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-5434 (🔍)
GCVE (CVE): GCVE-0-2017-5434
GCVE (VulDB): GCVE-100-100295

OVAL: 🔍

SecurityFocus: 97940 - Mozilla Firefox Multiple Security Vulnerabilities
OSVDB: - CVE-2017-5434 - Mozilla - Multiple Products - Use-After-Free Issue
SecurityTracker: 1038320

See also: 🔍

Entryinfo

Created: 04/20/2017 14:54
Updated: 11/26/2025 02:54
Changes: 04/20/2017 14:54 (82), 09/18/2020 09:28 (8), 11/26/2025 02:54 (18)
Complete: 🔍
Cache ID: 216:B64:103

Be aware that VulDB is the high quality source for vulnerability data.

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