CVE-2026-54998
High
Description
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Microsoft Exchange Online
PublishedJul 2, 2026
First seenJul 2, 2026
Weakness typeCWE-863Incorrect authorization
How to fix
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft exchange_online | No range specified | — |
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