Microsoft Windows up to Server 2019 CSRSS access control

CVSS Meta Temp Score
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CTI Interest Score
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6.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Microsoft Windows. It has been rated as critical. Affected by this issue is some unknown functionality of the component CSRSS. This manipulation causes access control. The identification of this vulnerability is CVE-2019-0735. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System). It has been declared as critical. Affected by this vulnerability is an unknown function of the component CSRSS. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

An elevation of privilege vulnerability exists when the Windows Client Server Run-Time Subsystem (CSRSS) fails to properly handle objects in memory, aka 'Windows CSRSS Elevation of Privilege Vulnerability'.

The bug was discovered 04/09/2019. The weakness was shared 04/09/2019 with Qihoo 360 Vulcan Team as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. The vendor cooperated in the coordination of the public release. This vulnerability is known as CVE-2019-0735 since 11/26/2018. The attack can be launched remotely. The successful exploitation requires a single authentication. Technical details are unknown but a public exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue. The advisory points out:

An elevation of privilege vulnerability exists when the Windows Client Server Run-Time Subsystem (CSRSS) fails to properly handle objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application to take control of an affected system.

It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 91522 (Microsoft Windows Security Update for April 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 vulnerability database at SecurityFocus (BID 107702†). The entries VDB-133162, VDB-133168, VDB-133177 and VDB-133179 are related to this item. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.8

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
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: 🔍
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NVD Base Score: 🔍

Exploitinginfo

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

Physical: Partially
Local: Yes
Remote: Yes

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

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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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: 🔍

Timelineinfo

11/26/2018 🔍
04/09/2019 +134 days 🔍
04/09/2019 +0 days 🔍
04/09/2019 +0 days 🔍
04/09/2019 +0 days 🔍
04/10/2019 +1 days 🔍
10/20/2025 +2385 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: 152532
Organization: Qihoo 360 Vulcan Team
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2019-0735 (🔍)
GCVE (CVE): GCVE-0-2019-0735
GCVE (VulDB): GCVE-100-133189
SecurityFocus: 107702 - Microsoft Windows MS XML CVE-2019-0790 Remote Code Execution Vulnerability

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

Entryinfo

Created: 04/10/2019 07:09
Updated: 10/20/2025 03:27
Changes: 04/10/2019 07:09 (74), 05/27/2020 20:53 (6), 08/27/2023 17:51 (5), 10/20/2025 03:27 (22)
Complete: 🔍
Cache ID: 216::103

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