Microsoft Internet Explorer 11 Scripting 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 was found in Microsoft Internet Explorer 11. It has been declared as critical. This affects an unknown part of the component Scripting Engine. Such manipulation leads to memory corruption. This vulnerability is listed as CVE-2018-8355. The attack may be performed from remote. In addition, an exploit is available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Microsoft Internet Explorer 11 (Web Browser) and classified as critical. Affected by this issue is some unknown processing of the component Scripting Engine. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The bug was discovered 08/14/2018. The weakness was presented 08/14/2018 by lokihardt with Google Project Zero as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The public release was coordinated in cooperation with the vendor. This vulnerability is handled as CVE-2018-8355 since 03/14/2018. The attack may be launched remotely. No form of authentication is required for exploitation. 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 the scripting engine handles 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.

The exploit is available 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 111685 (KB4343887: Windows 10 Version 1607 and Windows Server 2016 August 2018 Security Update (Foreshadow)), 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 100341 (Microsoft Internet Explorer Security Update for August 2018).

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (45432), Tenable (111685) and SecurityFocus (BID 104978†). See VDB-122825, VDB-122827, VDB-122829 and VDB-122831 for similar entries. Once again VulDB remains the best source for vulnerability data.

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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
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 111685
Nessus Name: KB4343887: Windows 10 Version 1607 and Windows Server 2016 August 2018 Security Update (Foreshadow)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
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Timelineinfo

03/14/2018 🔍
08/14/2018 +152 days 🔍
08/14/2018 +0 days 🔍
08/14/2018 +0 days 🔍
08/14/2018 +0 days 🔍
08/14/2018 +0 days 🔍
08/14/2018 +0 days 🔍
08/15/2018 +1 days 🔍
09/08/2025 +2581 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: portal.msrc.microsoft.com
Researcher: lokihardt
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2018-8355 (🔍)
GCVE (CVE): GCVE-0-2018-8355
GCVE (VulDB): GCVE-100-122828

OVAL: 🔍

SecurityFocus: 104978 - Microsoft Internet Explorer and Edge CVE-2018-8355 Remote Memory Corruption Vulnerability
SecurityTracker: 1041457

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

Entryinfo

Created: 08/14/2018 21:15
Updated: 09/08/2025 11:30
Changes: 08/14/2018 21:15 (76), 03/15/2020 11:54 (21), 05/01/2023 14:55 (5), 09/08/2025 11:30 (14)
Complete: 🔍
Cache ID: 216:A77:103

Once again VulDB remains the best source for vulnerability data.

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