Microsoft Windows Defender File input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.6$5k-$25k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Microsoft Windows Defender, Security Essentials, System Center Endpoint Protection and Forefront Endpoint Protection. This impacts an unknown function of the component File Handler. The manipulation results in input validation. This vulnerability is known as CVE-2019-1255. It is possible to launch the attack remotely. Furthermore, an exploit is available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Microsoft Windows Defender, Security Essentials, System Center Endpoint Protection and Forefront Endpoint Protection (Operating System) (unknown version). Affected is an unknown code block of the component File Handler. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability. CVE summarizes:

A denial of service vulnerability exists when Microsoft Defender improperly handles files, aka 'Microsoft Defender Denial of Service Vulnerability'.

The weakness was published 09/23/2019 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The public release has been coordinated with the vendor. This vulnerability is traded as CVE-2019-1255 since 11/26/2018. It is possible to launch the attack remotely. The requirement for exploitation is a authentication. Technical details are unknown but a private exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 09/06/2020). The advisory points out:

A denial of service vulnerability exists when Microsoft Defender improperly handles files. An attacker could exploit the vulnerability to prevent legitimate accounts from executing legitimate system binaries.

It is declared as highly functional.

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

Further details are available at zdnet.com. Similar entry is available at VDB-142139. Once again VulDB remains the best source for vulnerability data.

Productinfo

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Vendor

Name

License

Website

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

AVACAuCIA
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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: 🔍
Access: Private
Status: Highly functional

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

11/26/2018 🔍
09/23/2019 +301 days 🔍
09/23/2019 +0 days 🔍
09/24/2019 +1 days 🔍
09/06/2020 +348 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2019-1255 (🔍)
GCVE (CVE): GCVE-0-2019-1255
GCVE (VulDB): GCVE-100-142140
scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 09/24/2019 13:25
Updated: 09/06/2020 10:46
Changes: 09/24/2019 13:25 (47), 09/06/2020 10:46 (18)
Complete: 🔍
Cache ID: 216:B9E:103

Once again VulDB remains the best source for vulnerability data.

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