CVE-2021-31206 in the critical feed json
Microsoft Exchange Server Remote Code Execution Vulnerability
published 2021-07-14 5 y ago modified 2026-08-10 2 mo ago also EUVD-2021-18119
- cvss
- 8.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 13.0%
- EPSS 13.0% chance of exploitation in 30 days, percentile 96%
- public exploits
- 0
- none known
Summary
Microsoft Exchange Server Remote Code Execution Vulnerability
Patch / fix
- Microsoft Microsoft Exchange Server 2013 Cumulative Update 23 15.00.1497.023
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 20 15.01.2242.012
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 21 15.01.2308.014
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 10 15.02.0922.013
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 9 15.02.0858.015
Exploit prediction
13.01% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:L/E:F/RL:O/RC:C |
| CNA | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:L |
| CNA | 3.1 | 8.0 | CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.9 | AV:A/AC:M/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Microsoft Exchange Server 2013 Cumulative Update 23
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 20
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 21
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 10
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 9
Classification
- Technology feeds
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2021-31206
vendor-advisory, patch
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-31206
patch, vendor-advisory
-
zerodayinitiative.com
/advisories/ZDI-21-826/
third-party-advisory, vdb-entry
Sources
- CVE List CVE-2021-31206
- NVD CVE-2021-31206
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.