CVE-2026-55009
Microsoft Exchange Server Elevation of Privilege Vulnerability
HIGH 7.8
At a glance
- Source
- NVD
- EPSS
- EPSS 2.51 % · percentile 85 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- microsoft
- NVD status
- Analyzed
Description
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Weaknesses (CWE)
- CWE-502 — Deserialization of Untrusted Data
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C | microsoft |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · secure@microsoft.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-44027
- GCVE · GCVE-0-2026-55009
CERT-FR advisories
- CERTFR-2026-AVI-0872 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:*:*:*:*:*:*cpe:2.3:a:microsoft:exchange_server_subscription_edition:*:*:*:*:*:*:*:*< 15.02.2562.045
Affected products
| Product | Versions |
|---|---|
| Microsoft · Microsoft Exchange Server 2016 Cumulative Update 23 | affected 15.01.0.0 < 15.01.2507.071 |
| Microsoft · Microsoft Exchange Server 2019 Cumulative Update 14 | affected 15.02.0.0 < 15.02.1544.043 |
| Microsoft · Microsoft Exchange Server 2019 Cumulative Update 15 | affected 15.02.0.0 < 15.02.1748.048 |
| Microsoft · Microsoft Exchange Server Subscription Edition RTM | affected 15.02.0.0 < 15.02.2562.045 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |