Microsoft Edge on Win10/Server 2016 Javascript Engine PreVisitCatch memory corruption

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.8$0-$5k0.00

A vulnerability was found in Microsoft Edge on Win10/Server 2016 (Web Browser) (affected version not known). It has been declared as critical. Affected by this vulnerability is the function PreVisitCatch 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 Edge in Microsoft Windows 10 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-2017-8640, CVE-2017-8641, CVE-2017-8645, CVE-2017-8646, CVE-2017-8647, CVE-2017-8655, 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 disclosed 08/08/2017 with Google Project Zero as KB4034674 as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. This vulnerability is known as CVE-2017-8656 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 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 in Javascript 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). The code used by the exploit is:

function trigger() {
    try {
    } catch ({x}) {
        var x = 1;
    }
 
    print(x);
}
 
trigger();

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 (42464), Tenable (102264) and SecurityFocus (BID 100033†). The entries VDB-104989, VDB-104990, VDB-104991 and VDB-105007 are pretty similar. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

License

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

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

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

Local: No
Remote: Yes

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

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

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: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

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 +1 days 🔍
08/17/2017 +8 days 🔍
08/17/2017 +0 days 🔍
08/22/2024 +2562 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4034674
Researcher: Lokihart
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8656 (🔍)
GCVE (CVE): GCVE-0-2017-8656
GCVE (VulDB): GCVE-100-105037

OVAL: 🔍

SecurityFocus: 100033 - Microsoft Edge CVE-2017-8656 Scripting Engine Remote Memory Corruption Vulnerability
SecurityTracker: 1039095

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

Entryinfo

Created: 08/09/2017 12:07 PM
Updated: 08/22/2024 07:07 PM
Changes: 08/09/2017 12:07 PM (92), 11/09/2019 11:27 AM (12), 01/08/2021 07:53 AM (2), 01/08/2021 07:58 AM (1), 08/22/2024 07:07 PM (17)
Complete: 🔍
Cache ID: 18:5AC:40

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you want to use VulDB in your project?

Use the official API to access entries easily!