Microsoft Internet Explorer 9/10/11 Scripting Engine Compile 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 marked as critical has been reported in Microsoft Internet Explorer 9/10/11. Affected is the function jscript!RegExpComp::Compile of the component Scripting Engine. This manipulation causes memory corruption. This vulnerability is tracked as CVE-2017-11890. The attack is possible to be carried out remotely. Moreover, an exploit is present. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Internet Explorer 9/10/11 (Web Browser). It has been declared as critical. Affected by this vulnerability is the function jscript!RegExpComp::Compile of the component Scripting 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 Windows 7 SP1, Windows Server 2008 and R2 SP1, Windows 8.1 and Windows RT 8.1, Windows Server 2012 and R2, Windows 10 Gold, 1511, 1607, 1703, 1709, and Windows Server 2016 allow an attacker to execute arbitrary code in the context of the current user, due to how Internet Explorer handles objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-11886, CVE-2017-11889, CVE-2017-11893, CVE-2017-11894, CVE-2017-11895, CVE-2017-11901, CVE-2017-11903, CVE-2017-11905, CVE-2017-11907, CVE-2017-11908, CVE-2017-11909, CVE-2017-11910, CVE-2017-11911, CVE-2017-11912, CVE-2017-11913, CVE-2017-11914, CVE-2017-11916, CVE-2017-11918, and CVE-2017-11930.

The bug was discovered 12/12/2017. The weakness was disclosed 12/12/2017 by Ivan Fratric with Google Project Zero as KB4054519 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is known as CVE-2017-11890 since 07/31/2017. 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 when Internet Explorer improperly accesses 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. 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, the attacker 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 1 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 105184 (Windows 7 and Windows Server 2008 R2 December 2017 Security Updates), 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 100325 (Microsoft Internet Explorer Security Update for December 2017). The code used by the exploit is:

<!-- saved from url=(0014)about:internet -->
<html>
<head>
<meta http-equiv="X-UA-Compatible" content="IE=8"></meta>
</head>
<body>
<script language="Jscript.Encode">
 
var s = 'a';
for(var i=0;i<28;i++) {
  s = s+s;
}
s = s+'[a-z]'+s;
 
r = new RegExp();
r.compile(s);
 
</script>
</body>
</html>

Applying the patch KB4054519 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 (43369), Tenable (105184) and SecurityFocus (BID 102082†). The entries VDB-110522, VDB-110523, VDB-110524 and VDB-110529 are pretty similar. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

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

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp 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: 105184
Nessus Name: Windows 7 and Windows Server 2008 R2 December 2017 Security Updates
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 863099
OpenVAS Name: Microsoft Internet Explorer Multiple Vulnerabilities (KB4052978)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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Patch: KB4054519

Timelineinfo

07/31/2017 🔍
12/12/2017 +134 days 🔍
12/12/2017 +0 days 🔍
12/12/2017 +0 days 🔍
12/12/2017 +0 days 🔍
12/12/2017 +0 days 🔍
12/12/2017 +0 days 🔍
12/13/2017 +1 days 🔍
12/19/2017 +6 days 🔍
12/19/2017 +0 days 🔍
12/29/2025 +2932 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4054519
Researcher: Ivan Fratric
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11890 (🔍)
GCVE (CVE): GCVE-0-2017-11890
GCVE (VulDB): GCVE-100-110527

OVAL: 🔍

SecurityFocus: 102082 - Microsoft Internet Explorer CVE-2017-11890 Remote Memory Corruption Vulnerability
SecurityTracker: 1039991

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

Entryinfo

Created: 12/13/2017 07:48
Updated: 12/29/2025 21:15
Changes: 12/13/2017 07:48 (101), 12/16/2019 10:54 (7), 01/26/2021 19:11 (2), 12/29/2025 21:15 (15)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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