Microsoft Edge on Win10/Server 2016 Javascript Engine 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 labeled as critical has been found in Microsoft Edge on Win10/Server 2016. The impacted element is an unknown function of the component Javascript Engine. The manipulation results in memory corruption. This vulnerability is cataloged as CVE-2017-8640. The attack may be launched remotely. Furthermore, there is an exploit available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in Microsoft Edge on Win10/Server 2016 (Web Browser) (the affected version unknown). Affected is an unknown part 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 Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 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-2017-8634, CVE-2017-8635, CVE-2017-8636, CVE-2017-8638, CVE-2017-8639, 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 shared 08/08/2017 with Google Project Zero as KB4034668 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability is traded as CVE-2017-8640 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 are unknown but a public exploit is available. 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 102264 (KB4034658: Windows 10 Version 1607 and Windows Server 2016 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 KB4034668 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 (42476), Tenable (102264) and SecurityFocus (BID 100051†). The entries VDB-104989, VDB-104990, VDB-104991 and VDB-105007 are related to this item. VulDB is the best source for vulnerability data and more expert information about this specific topic.

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: 102264
Nessus Name: KB4034658: Windows 10 Version 1607 and Windows Server 2016 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

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
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Exploit Delay Time: 🔍

Patch: KB4034668

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 +1 days 🔍
08/17/2017 +8 days 🔍
08/17/2017 +0 days 🔍
12/14/2025 +3041 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4034668
Researcher: Lokihart
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8640 (🔍)
GCVE (CVE): GCVE-0-2017-8640
GCVE (VulDB): GCVE-100-105024

OVAL: 🔍

SecurityFocus: 100051 - Microsoft Edge CVE-2017-8640 Scripting Engine Remote Memory Corruption Vulnerability
SecurityTracker: 1039095

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

Entryinfo

Created: 08/09/2017 12:00
Updated: 12/14/2025 04:53
Changes: 08/09/2017 12:00 (91), 11/09/2019 10:27 (12), 01/07/2021 18:49 (2), 01/07/2021 18:54 (1), 12/14/2025 04:53 (15)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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