CVE-2020-0688
Improper Authentication
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, aka 'Microsoft Exchange Memory Corruption Vulnerability'.
Official description from the CVE record, published by microsoft. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org
Key data
CVSS 3.1 High 8.8
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: Low
A basic user account is needed.
User interaction: None
No action from any user is needed.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.
| Metric | Value | What it means |
|---|---|---|
| Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. |
| Privileges required | Low | A basic user account is needed. |
| User interaction | None | No action from any user is needed. |
| Scope | Unchanged | The impact stays within the vulnerable component. |
| Confidentiality impact | High | Serious or total effect on the secrecy of data. |
| Integrity impact | High | Serious or total effect on the trustworthiness of data. |
| Availability impact | High | Serious or total effect on availability. |
CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.
EPSS
- Score
- 0.99955 (99.95% probability)
- Percentile
- 99.97%
- Scores of
- Nov 10, 2026
- Model
- v2026.06.15
CISA Known Exploited Vulnerabilities
- Name in the catalog
- Microsoft Exchange Server Validation Key Remote Code Execution Vulnerability
- Added to the catalog
- Nov 3, 2021
- Federal due date
- May 3, 2022
- Ransomware campaigns
- Known use
CISA assessment as of Feb 4, 2025
- Exploitation
- Recorded by CISA as active
- Automatable
- no
- Technical impact
- total
Weakness (CWE)
- CWE-287Improper Authentication
Affected products
Microsoft Exchange Server 2013
- affected: Cumulative Update 23
Microsoft Exchange Server 2019 Cumulative Update 3
- affected: unspecified
Microsoft Exchange Server 2016 Cumulative Update 14
- affected: unspecified
Microsoft Exchange Server 2016 Cumulative Update 15
- affected: unspecified
Microsoft Exchange Server 2019 Cumulative Update 4
- affected: unspecified
Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 30
- affected: unspecified
References
Timeline
- ID reserved
- Record published
- Added to CISA KEV
- Record last updated
Look up another CVE
About CubePath
Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:35 UTC. Sources and licenses