CVE-2021-28481 in the critical feed json
Microsoft Exchange Server Remote Code Execution Vulnerability
published 2021-04-13 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-15159
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 36.2%
- EPSS 36.2% chance of exploitation in 30 days, percentile 98%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
Microsoft Exchange Server Remote Code Execution Vulnerability
Patch / fix
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 9 15.02.0858.010
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 20 15.01.2242.008
- Microsoft Microsoft Exchange Server 2013 Cumulative Update 23 15.00.1497.015
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 19 15.01.2176.012
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 8 15.02.0792.013
Exploit prediction
36.24% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- Nuclei template Microsoft Exchange - Pre-Auth SSRF / ACL Bypass (ProxyNotFound) nuclei detection template
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 10.0 | AV:N/AC:L/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 9
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 20
- Microsoft Microsoft Exchange Server 2013 Cumulative Update 23
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 19
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 8
Classification
- Technology feeds
References
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-28481
patch, vendor-advisory
Sources
- CVE List CVE-2021-28481
- NVD CVE-2021-28481
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