Microsoft Exchange Server 2019 Cumulative Update 9

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

Product reference — Microsoft Exchange Server 2019 Cumulative Update 9 by Microsoft · sector: Operating Systems & Platforms. Cumulative disclosure record for this product across the archive.

Product totals

Disclosures & known-exploited
	All-time	YTD
CVEs	6	0
KEV entries	4	0

Rate & severity
KEV/100	Med CVSS	Med EPSS	C	H	M	L
66.7	7.8	.7612	2	4	0	0

KEV/100 = KEV entries ÷ CVEs × 100. Med CVSS / Med EPSS are medians over this product's disclosures. C/H/M/L = disclosures by CVSS severity band.

Monthly disclosures

Trend (by first-seen month, full archive): █▁▁▁█▁▅▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▅▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

Last 12 months (new CVEs by first-seen day)
Month	New CVEs
2025-09	0
2025-10	0
2025-11	0
2025-12	0
2026-01	0
2026-02	0
2026-03	0
2026-04	0
2026-05	0
2026-06	0
2026-07	0
2026-08	0

Notable CVEs

Ranked by the published formula: KEV → EPSS → CVSS → CVE ID.

Notable (ranked)
CVE	CVSS	EPSS %ile	Severity	KEV	First seen
CVE-2021-34473	9.1	100.0	CRITICAL	YES	2021-11-03
CVE-2021-34523	9.0	100.0	CRITICAL	YES	2021-11-03
CVE-2021-33766	7.3	99.9	HIGH	YES	2022-01-18
CVE-2021-31196	7.2	98.9	HIGH	YES	2024-08-21
CVE-2021-31206	7.6	96.0	HIGH	—	2021-07-14
CVE-2021-33768	8.0	67.9	HIGH	—	2021-07-14

Recent CVEs

Most recently seen
CVE	CVSS	EPSS %ile	Severity	KEV	First seen
CVE-2021-31196	7.2	98.9	HIGH	YES	2024-08-21
CVE-2021-33766	7.3	99.9	HIGH	YES	2022-01-18
CVE-2021-34523	9.0	100.0	CRITICAL	YES	2021-11-03
CVE-2021-34473	9.1	100.0	CRITICAL	YES	2021-11-03
CVE-2021-33768	8.0	67.9	HIGH	—	2021-07-14
CVE-2021-31206	7.6	96.0	HIGH	—	2021-07-14

KEV entries

CISA Known Exploited Vulnerabilities (newest addition first)
CVE	KEV added	CVSS	EPSS %ile	Severity
CVE-2021-31196	2024-08-21	7.2	98.9	HIGH
CVE-2021-33766	2022-01-18	7.3	99.9	HIGH
CVE-2021-34523	2021-11-03	9.0	100.0	CRITICAL
CVE-2021-34473	2021-11-03	9.1	100.0	CRITICAL

Vendor: Microsoft — all products and the full vendor record.

Methodology

A product is a (vendor, product) pair as named in the affected-product data. Rate statistics are arithmetic over published figures. Counts key to first-seen day. Raw counts are not comparable across products; this is a reference page assembled from the public record, not a ranking by our judgment.