CVE-2026-54998: Microsoft Exchange Online Elevation of Privilege Vulnerability
This Microsoft advisory covers CVE-2026-54998 in Microsoft Exchange Online.
- CVE-2026-54998
Key facts
- Vendor rating
- High, CVSS 8.8
- CISA KEV
- Not listed (catalogue checked )
- Affected
- Microsoft Exchange Online -
- Source published
- Source revised
- Listed by VulniPulse
Compiled by VulniPulse from the linked sources. How records are collected and checked.
Affected products & platforms
Description
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
Text from the source record.
- Microsoft Exchange Online -
Official advisory · high-confidence parse· fetched ·verify at source
End-of-life dates for Microsoft Exchange Server
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Microsoft Server advisories, July 2026All Microsoft Server advisories
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