7.8
High
CVE-2026-55009 Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges…
Description
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft Exchange Server 2016 Cumulative Update 23 15.01 | 15.01.0.0 → < 15.01.2507.071 | 15.01.2507.071 |
| Microsoft Exchange Server 2019 Cumulative Update 14 15.02 | 15.02.0.0 → < 15.02.1544.043 | 15.02.1544.043 |
| Microsoft Exchange Server 2019 Cumulative Update 15 15.02 | 15.02.0.0 → < 15.02.1748.048 | 15.02.1748.048 |
| Microsoft Exchange Server Subscription Edition RTM 15.02 | 15.02.0.0 → < 15.02.2562.045 | 15.02.2562.045 |
Other CVEs of Microsoft Exchange Server 2016 Cumulative Update 23
The 88 CVEs of Microsoft Exchange Server 2016 Cumulative Update 23 →
CVE-2026-87695
Inclusion of functionality from untrusted control sphere in Microsoft Exchange Server allows an authorized attacker to…
7.8
High
CVE-2026-87692
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges…
7.8
High
CVE-2026-70279
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows…
9.3
Critical
CVE-2026-87696
Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate…
7.5
High