Double Free in Microsoft Exchange Server 2019 Cumulative Update 14

CVE-2026-55007

Double free in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.

Vulnerability class: Double Free

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55007?
CVE-2026-55007 is a high-severity vulnerability in Microsoft Exchange Server 2019 Cumulative Update 14, classified under Double Free. CVSS score: 8.1/10. Published 2026-09-08.
How severe is CVE-2026-55007?
High severity. CVSS v3 base score is 8.1 out of 10.