VDB-123825 · CVE-2018-8420 · BID 105259

Microsoft Windows up to Server 2016 MSXML Parser xml external entity reference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$0-$5k0.00

A vulnerability, which was classified as critical, was found in Microsoft Windows (Operating System). This affects some unknown functionality of the component MSXML Parser. The manipulation with an unknown input leads to a xml external entity reference vulnerability. CWE is classifying the issue as CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. This is going to have an impact on confidentiality, integrity, and availability.

The bug was discovered 09/11/2018. The weakness was published 09/11/2018 with Zero Day Initiative as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. The public release has been coordinated with Microsoft. This vulnerability is uniquely identified as CVE-2018-8420 since 03/14/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/08/2023). The advisory points out:

A remote code execution vulnerability exists when the Microsoft XML Core Services MSXML parser processes user input. An attacker who successfully exploited the vulnerability could run malicious code remotely to take control of the user’s system.

The vulnerability scanner Nessus provides a plugin with the ID 117415 (KB4457140: Windows Server 2012 September 2018 Security 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 371164 (Microsoft Windows Security Update September 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 vulnerability database at Tenable (117415). Similar entries are available at 123823, 123827, 123828 and 123831.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.5
Vendor Vector (Microsoft): 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Xml external entity reference
CWE: CWE-611 / CWE-610
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 117415
Nessus Name: KB4457140: Windows Server 2012 September 2018 Security Update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

03/14/2018 🔍
09/11/2018 +180 days 🔍
09/11/2018 +0 days 🔍
09/11/2018 +0 days 🔍
09/11/2018 +0 days 🔍
09/11/2018 +0 days 🔍
09/12/2018 +0 days 🔍
09/12/2018 +0 days 🔍
05/08/2023 +1699 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: portal.msrc.microsoft.com
Organization: Zero Day Initiative
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2018-8420 (🔍)
SecurityTracker: 1041627
SecurityFocus: 105259 - Microsoft Windows XML Core Services MSXML parser CVE-2018-8420 Remote Code Execution Vulnerability

scip Labs: https://www.scip.ch/en/?labs.20161215
See also: 🔍

Entryinfo

Created: 09/12/2018 07:11 AM
Updated: 05/08/2023 09:39 AM
Changes: 09/12/2018 07:11 AM (85), 03/22/2020 01:35 PM (6), 05/08/2023 09:39 AM (5)
Complete: 🔍
Submitter: edward.zhong

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