VDB-134705 · CVE-2019-0820 · RHSA-2019:1259

Microsoft .NET Framework/.NET Core Regex input validation

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5.8	$0-$5k	0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Microsoft .NET Framework and .NET Core. Affected is an unknown function of the component Regex Handler. The manipulation leads to input validation. This vulnerability is referenced as CVE-2019-0820. Remote exploitation of the attack is possible. No exploit is available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Microsoft .NET Framework and .NET Core (Programming Language Software) (the affected version is unknown). This issue affects an unknown code of the component Regex Handler. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is availability. The summary by CVE is:

A denial of service vulnerability exists when .NET Framework and .NET Core improperly process RegEx strings, aka '.NET Framework and .NET Core Denial of Service Vulnerability'. This CVE ID is unique from CVE-2019-0980, CVE-2019-0981.

The bug was discovered 05/14/2019. The weakness was published 05/14/2019 as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. The public release has been coordinated with Microsoft. The identification of this vulnerability is CVE-2019-0820 since 11/26/2018. The attack may be initiated remotely. A simple authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The advisory points out:

A denial of service vulnerability exists when .NET Framework and .NET Core improperly process RegEx strings. An attacker who successfully exploited this vulnerability could cause a denial of service against a .NET application.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 91531 (Microsoft .NET Framework and .NET Core Denial of Service Vulnerability May 2019).

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

Similar entries are available at VDB-134707, VDB-134748 and VDB-134749. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Programming Language Software

Vendor

Microsoft

Name

License

free

Website

Vendor: https://www.microsoft.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

11/26/2018 🔍
05/14/2019 +169 days 🔍
05/14/2019 +0 days 🔍
05/14/2019 +0 days 🔍
05/15/2019 +1 days 🔍
09/17/2023 +1586 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: RHSA-2019:1259
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2019-0820 (🔍)
GCVE (CVE): GCVE-0-2019-0820
GCVE (VulDB): GCVE-100-134705
See also: 🔍

Entryinfo

Created: 05/15/2019 07:00
Updated: 09/17/2023 10:57
Changes: 05/15/2019 07:00 (62), 06/09/2020 17:43 (3), 09/17/2023 10:57 (4)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.