VDB-170979 · CVE-2021-26876 · GCVE-0-2021-26876

Microsoft Windows up to Server 2019 OpenType Font Parser code injection

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.0	$5k-$25k	0.00

Summaryinfo

A vulnerability marked as critical has been reported in Microsoft Windows up to Server 2019. The affected element is an unknown function of the component OpenType Font Parser. Performing a manipulation results in an unknown weakness. This vulnerability is cataloged as CVE-2021-26876. It is possible to initiate the attack remotely. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in Microsoft Windows up to Server 2019 (Operating System). It has been classified as critical. This affects an unknown code of the component OpenType Font Parser. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was shared 03/09/2021 as confirmed security guidance (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2021-26876. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/30/2021). The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

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

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Operating System

Vendor

Microsoft

Name

Windows

Version

License

commercial

Website

Vendor: https://www.microsoft.com/
Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.3

VulDB Base Score: 6.3
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 8.8
Vendor Vector (Microsoft): 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

NVD Base Score: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

02/08/2021 🔍
03/09/2021 +29 days 🔍
03/09/2021 +0 days 🔍
03/10/2021 +0 days 🔍
03/30/2021 +20 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

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

CVE: CVE-2021-26876 (🔍)
GCVE (CVE): GCVE-0-2021-26876
GCVE (VulDB): GCVE-100-170979
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 03/10/2021 12:21
Updated: 03/30/2021 11:08
Changes: 03/10/2021 12:21 (30), 03/10/2021 12:25 (24), 03/30/2021 11:02 (2), 03/30/2021 11:08 (20)
Complete: 🔍
Cache ID: 216::103