Microsoft Edge on Win10 Javascript Engine ConcatArgs memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Microsoft Edge on Win10 and classified as critical. Affected by this issue is the function JavascriptArray::ConcatArgs of the component Javascript Engine. The manipulation results in memory corruption. This vulnerability was named CVE-2017-8634. The attack may be performed from remote. In addition, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in Microsoft Edge on Win10 (Web Browser) (the affected version is unknown). It has been classified as critical. Affected is the function JavascriptArray::ConcatArgs of the component Javascript Engine. 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. CVE summarizes:

Microsoft Edge in Microsoft Windows 10 1703 allows an attacker to execute arbitrary code in the context of the current user due to the way that Microsoft browser JavaScript engines render content when handling objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-8635, CVE-2017-8636, CVE-2017-8638, CVE-2017-8639, CVE-2017-8640, CVE-2017-8641, CVE-2017-8645, CVE-2017-8646, CVE-2017-8647, CVE-2017-8655, CVE-2017-8656, CVE-2017-8657, CVE-2017-8670, CVE-2017-8671, CVE-2017-8672, and CVE-2017-8674.

The bug was discovered 08/08/2017. The weakness was presented 08/08/2017 with Qihoo 360 as KB4034674 as confirmed security update guide (Website). The advisory is available at portal.msrc.microsoft.com. This vulnerability is traded as CVE-2017-8634 since 05/03/2017. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. Technical details and a public exploit are known. The advisory points out:

A remote code execution vulnerability exists in the way that Microsoft browser JavaScript engines render content when handling objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user.

A public exploit has been developed by Google Security Research and been published 2 weeks after the advisory. The exploit is shared for download at exploit-db.com. 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 102269 (KB4034674: Windows 10 Version 1703 August 2017 Cumulative Update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 91406 (Microsoft Edge Security Update for August 2017).

Applying the patch KB4034674 is able to eliminate this problem. The bugfix is ready for download at catalog.update.microsoft.com. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (42474), Tenable (102269) and SecurityFocus (BID 100043†). See VDB-105007, VDB-105009, VDB-105010 and VDB-105012 for similar entries. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.8

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 4.2
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Google Security Research
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 102269
Nessus Name: KB4034674: Windows 10 Version 1703 August 2017 Cumulative Update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 802136
OpenVAS Name: Microsoft Windows Multiple Vulnerabilites (KB4034674)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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Patch: KB4034674

Timelineinfo

05/03/2017 🔍
08/08/2017 +97 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/09/2017 +0 days 🔍
08/17/2017 +8 days 🔍
08/17/2017 +0 days 🔍
12/14/2025 +3041 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4034674
Researcher: Hao Linan
Organization: Qihoo 360
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8634 (🔍)
GCVE (CVE): GCVE-0-2017-8634
GCVE (VulDB): GCVE-100-105018

OVAL: 🔍

SecurityFocus: 100043 - Microsoft Edge CVE-2017-8634 Scripting Engine Remote Memory Corruption Vulnerability
SecurityTracker: 1039095

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 08/09/2017 11:55
Updated: 12/14/2025 04:53
Changes: 08/09/2017 11:55 (92), 11/09/2019 10:43 (12), 01/07/2021 17:58 (2), 01/07/2021 18:01 (1), 12/14/2025 04:53 (15)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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