Microsoft Exchange Server up to 2019 CU9 input validation

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 (≈)
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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.
7.5$5k-$25k0.00

Summaryinfo

A vulnerability was found in Microsoft Exchange Server 2013 CU23/2016 CU19/2016 CU20/2019 CU8/2019 CU9. It has been classified as critical. This vulnerability affects unknown code. Performing a manipulation results in an unknown weakness. This vulnerability is reported as CVE-2021-31198. The attack is possible to be carried out remotely. No exploit exists. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in Microsoft Exchange Server 2013 CU23/2016 CU19/2016 CU20/2019 CU8/2019 CU9 (Groupware Software). 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 confidentiality, integrity, and availability.

The weakness was disclosed 05/11/2021 as confirmed security guidance (Website). The advisory is shared at portal.msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2021-31198. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/01/2025).

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.1
VulDB Meta Temp Score: 7.5

VulDB Base Score: 8.8
VulDB Temp Score: 7.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.8
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector (Microsoft): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Unproven

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

04/14/2021 🔍
05/11/2021 +27 days 🔍
05/11/2021 +0 days 🔍
05/12/2021 +0 days 🔍
03/01/2025 +1389 days 🔍

Sourcesinfo

Vendor: microsoft.com

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

CVE: CVE-2021-31198 (🔍)
GCVE (CVE): GCVE-0-2021-31198
GCVE (VulDB): GCVE-100-174837

Entryinfo

Created: 05/12/2021 06:34
Updated: 03/01/2025 02:39
Changes: 05/12/2021 06:34 (33), 05/12/2021 06:38 (20), 05/13/2021 12:39 (2), 03/01/2025 02:39 (44)
Complete: 🔍
Cache ID: 216::103

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