Microsoft Windows up to Server 2019 AppContainer Sandbox XmlDocument access control

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Microsoft Windows. This affects the function XmlDocument of the component AppContainer Sandbox. The manipulation results in access control. This vulnerability is cataloged as CVE-2019-0555. The attack must be initiated from a local position. Furthermore, there is an exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System). It has been classified as critical. Affected is the function XmlDocument of the component AppContainer Sandbox. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on confidentiality, integrity, and availability.

The bug was discovered 01/08/2019. The weakness was shared 01/08/2019 by James Forshaw with Google Project Zero as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The vendor cooperated in the coordination of the public release. This vulnerability is traded as CVE-2019-0555 since 11/26/2018. The exploitability is told to be difficult. The attack needs to be approached locally. The successful exploitation needs a authentication. Technical details and a public exploit are known. The MITRE ATT&CK project declares the attack technique as T1068. The advisory points out:

An elevation of privilege vulnerability exists in the Microsoft XmlDocument class that could allow an attacker to escape from the AppContainer sandbox in the browser. An attacker who successfully exploited this vulnerability could gain elevated privileges and break out of the Edge AppContainer sandbox.

The exploit is shared for download 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 121011 (KB4480116: Windows 10 Version 1809 and Windows Server 2019 January 2019 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 91495 (Microsoft Windows Security Update January 2019).

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 (46185), Tenable (121011) and SecurityFocus (BID 106395†). The entries VDB-128717, VDB-128718, VDB-128719 and VDB-128720 are related to this item. Once again VulDB remains the best 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: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.0
VulDB Temp Score: 6.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.0
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 121011
Nessus Name: KB4480116: Windows 10 Version 1809 and Windows Server 2019 January 2019 Security Update
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: 🔍
0-Day Time: 🔍
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Timelineinfo

11/26/2018 🔍
01/08/2019 +43 days 🔍
01/08/2019 +0 days 🔍
01/08/2019 +0 days 🔍
01/08/2019 +0 days 🔍
01/08/2019 +0 days 🔍
01/08/2019 +0 days 🔍
01/08/2019 +0 days 🔍
10/19/2025 +2476 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

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

CVE: CVE-2019-0555 (🔍)
GCVE (CVE): GCVE-0-2019-0555
GCVE (VulDB): GCVE-100-128724
SecurityFocus: 106395 - Microsoft Windows CVE-2019-0555 Local Privilege Escalation Vulnerability

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

Entryinfo

Created: 01/08/2019 21:55
Updated: 10/19/2025 21:11
Changes: 01/08/2019 21:55 (86), 04/26/2020 12:39 (10), 06/23/2023 09:06 (4), 10/19/2025 21:11 (14)
Complete: 🔍
Cache ID: 216::103

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