Microsoft Exchange Server 2016 Cumulative Update 21

productUS

A product tracked in the threat graph; the vulnerabilities below are known to affect it.

unpatched

by severity

1critical3high8medium0low

updated 2026-10-27

vulnerabilities (12)

Related CVEs.

sort

ID	severity	EPSS	exploitable	patched	published	affected
CVE-2021-42321US	medium6.5OT critical	91.7% (100th)	KEV	15.01.2308.020	2021-11-10	2 versions
CVE-2021-31196US	medium6.5OT critical	54.1% (99th)	KEV	15.01.2308.014	2021-07-14	2 versions
CVE-2021-41349US	medium4.3	93.5% (100th)	Exploit	15.01.2308.020	2021-11-10	2 versions
CVE-2022-23277US	medium6.5	41.1% (99th)	Exploit	15.01.2308.027	2022-03-09	2 versions
CVE-2021-34470US	medium5.2	4.38% (91st)	Exploit	15.01.2308.008	2021-07-14	2 versions
CVE-2022-24463US	medium4.0	31.8% (98th)	—	15.01.2308.027	2022-03-09	2 versions
CVE-2021-31206US	high7.9	13.0% (96th)	—	15.01.2308.014	2021-07-14	2 versions
CVE-2021-42305US	medium4.3	7.87% (95th)	—	15.01.2308.020	2021-11-10	2 versions
CVE-2021-33768US	medium5.2	1.23% (69th)	—	15.01.2308.014	2021-07-14	2 versions
CVE-2022-21969US	critical9.0	1.12% (66th)	—	15.01.2308.021	2022-01-11	2 versions
CVE-2022-21846US	high8.3	1.06% (64th)	—	15.01.2308.021	2022-01-11	2 versions
CVE-2022-21855US	high7.7	0.93% (60th)	—	15.01.2308.021	2022-01-11	2 versions

The flaw types (CWEs) most of these CVEs share.

Which sources assert this record, and when.

scry

Products carry known vulnerabilities once they are exposed to the internet. See what is exposed on your perimeter with a free passive scan.