CVEs / CVE-2020-0688
CVE-2020-0688: Microsoft Exchange Server Validation Key Remote Code Execution Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- high 8.8 CVSS 3.1 (NVD)
- EPSS 99.9% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Exchange Server Validation Key fails to properly create unique keys at install time, allowing for remote code execution.
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'.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft Exchange Server 2013 | Cumulative Update 23 | — |
| Microsoft Microsoft Exchange Server 2019 Cumulative Update 3 | unspecified | — |
| Microsoft Microsoft Exchange Server 2016 Cumulative Update 14 | unspecified | — |
| Microsoft Microsoft Exchange Server 2016 Cumulative Update 15 | unspecified | — |
| Microsoft Microsoft Exchange Server 2019 Cumulative Update 4 | unspecified | — |
| Microsoft Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 30 | unspecified | — |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 3 May 2022 |
| Used in ransomware campaigns | Known |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-287 |
References
- CVE-2020-0688 on NVD
- CVE-2020-0688 in the CISA KEV catalog
- http://packetstormsecurity.com/files/156592/Microsoft-Exchange-2019-15.2.221.12-Remote-Code-Execution.html Exploit, Third Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/156620/Exchange-Control-Panel-Viewstate-Deserialization.html Exploit, Third Party Advisory, VDB Entry
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0688 Patch, Vendor Advisory
- https://www.zerodayinitiative.com/advisories/ZDI-20-258/ Third Party Advisory, VDB Entry
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0688 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.