8.8
High
CVE-2026-54998 Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network
Description
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft Exchange Online | Versions not published |
References
- Microsoft Exchange Online Elevation of Privilege Vulnerability msrc.microsoft.com
Timeline
- Published
- Last modified
Other CVEs of Microsoft Exchange Online
The 7 CVEs of Microsoft Exchange Online →
CVE-2026-96185
Stack-based buffer overflow in Microsoft Exchange Online allows an authorized attacker to execute code over a network
7.5
High
CVE-2026-65801
Server-side request forgery (ssrf) in Microsoft Exchange Online allows an unauthorized attacker to elevate privileges…
10.0
Critical
CVE-2026-56191
Improper authentication in Microsoft Exchange Online allows an unauthorized attacker to perform tampering over a network
10.0
Critical
CVE-2026-48582
Missing authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network
9.6
Critical