Microsoft Windows up to Server 2019 Kernel Cryptography Driver cng.sys CfgAdtpFormatPropertyBlock buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.7$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical has been found in Microsoft Windows. Affected by this issue is the function CfgAdtpFormatPropertyBlock of the file cng.sys of the component Kernel Cryptography Driver. Performing a manipulation results in buffer overflow. This vulnerability is identified as CVE-2020-17087. Additionally, an exploit exists. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System). It has been classified as critical. This affects the function CfgAdtpFormatPropertyBlock of the file cng.sys of the component Kernel Cryptography Driver. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was released 10/31/2020 by Mateusz Jurczyk and Sergei Glazunov with Google Project Zero (https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17087). The advisory is shared at bugs.chromium.org. This vulnerability is uniquely identified as CVE-2020-17087. The exploitability is told to be easy. Technical details and a private exploit are known. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 02/05/2025).

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 05/03/2022:

Apply updates per vendor instructions.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at Zero-Day.cz (586). Further details are available at twitter.com. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Access: Private
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/04/2020 🔍
10/31/2020 +88 days 🔍
10/31/2020 +0 days 🔍
02/05/2025 +1558 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: bugs.chromium.org
Researcher: Mateusz Jurczyk, Sergei Glazunov
Organization: Google Project Zero
Status: Confirmed

CVE: CVE-2020-17087 (🔍)
GCVE (CVE): GCVE-0-2020-17087
GCVE (VulDB): GCVE-100-164121
scip Labs: https://www.scip.ch/en/?labs.20161215
Misc.: 🔍

Entryinfo

Created: 10/31/2020 16:27
Updated: 02/05/2025 07:57
Replaces Duplicates: 🔍
Changes: 10/31/2020 16:27 (39), 10/31/2020 16:28 (5), 11/30/2020 20:04 (2), 11/30/2020 20:06 (18), 12/21/2022 09:39 (5), 04/20/2024 21:20 (24), 07/01/2024 05:31 (2), 09/09/2024 22:29 (3), 02/05/2025 07:57 (12)
Complete: 🔍
Cache ID: 216::103

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

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