Microsoft Internet Explorer/Edge Javascript Engine TryUndeleteProperty memory corruption

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

Summaryinfo

A vulnerability was found in Microsoft Internet Explorer and Edge. It has been classified as critical. This affects the function TryUndeleteProperty of the component Javascript Engine. This manipulation causes memory corruption. The identification of this vulnerability is CVE-2017-8635. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in Microsoft Internet Explorer and Edge (Web Browser) (unknown version). It has been declared as critical. Affected by this vulnerability is the function TryUndeleteProperty of the component Javascript 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. The summary by CVE is:

Microsoft browsers in Microsoft Windows 7 SP1, Windows Server 2008 R2 SP1, Windows 8.1 and Windows RT 8.1, Windows Server 2012 and R2, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 allow an attacker to execute arbitrary code in the context of the current user due to the way that JavaScript engines render when handling objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-8634, 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 shared 08/08/2017 with Google Project Zero as KB4034674 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is known as CVE-2017-8635 since 05/03/2017. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details and also a public exploit are known. The advisory points out:

A remote code execution vulnerability exists in the way JavaScript engines render when handling objects in memory in Microsoft browsers. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

A public exploit has been developed by Google Security Research and been published 2 weeks after the advisory. It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $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 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 (42471), Tenable (102264) and SecurityFocus (BID 100055†). The entries VDB-104989, VDB-104990, VDB-104991 and VDB-105007 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

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CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

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

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

Vendor Base Score (Microsoft): 7.5
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: 802286
OpenVAS Name: Microsoft Internet Explorer Multiple Vulnerabilities (KB4034733)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Patch
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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: Lokihart
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8635 (🔍)
GCVE (CVE): GCVE-0-2017-8635
GCVE (VulDB): GCVE-100-105019

OVAL: 🔍

SecurityFocus: 100055 - Microsoft Internet Explorer and Edge CVE-2017-8635 Remote Memory Corruption Vulnerability
SecurityTracker: 1039094

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

Entryinfo

Created: 08/09/2017 11:56
Updated: 12/14/2025 04:53
Changes: 08/09/2017 11:56 (91), 11/09/2019 10:58 (12), 01/07/2021 18:04 (2), 01/07/2021 18:11 (1), 12/14/2025 04:53 (15)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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