CVE-2026-54998: CWE-863: Incorrect Authorization in Microsoft Microsoft Exchange Online
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
AI Analysis
Technical Summary
This vulnerability, identified as CVE-2026-54998 and classified under CWE-863 (Incorrect Authorization), affects Microsoft Exchange Online. It allows an attacker who already has some level of authorization to escalate their privileges remotely without user interaction. The vulnerability has a high impact on confidentiality, integrity, and availability. Microsoft has released an official fix to remediate this issue.
Potential Impact
An authorized attacker can exploit this vulnerability to elevate their privileges within Microsoft Exchange Online, potentially gaining unauthorized access to sensitive information and performing unauthorized actions. The vulnerability impacts confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the patch provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54998 to remediate this vulnerability.
CVE-2026-54998: CWE-863: Incorrect Authorization in Microsoft Microsoft Exchange Online
Description
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
CVSS v3.1
Score 8.8high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CVE-2026-54998 and classified under CWE-863 (Incorrect Authorization), affects Microsoft Exchange Online. It allows an attacker who already has some level of authorization to escalate their privileges remotely without user interaction. The vulnerability has a high impact on confidentiality, integrity, and availability. Microsoft has released an official fix to remediate this issue.
Potential Impact
An authorized attacker can exploit this vulnerability to elevate their privileges within Microsoft Exchange Online, potentially gaining unauthorized access to sensitive information and performing unauthorized actions. The vulnerability impacts confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the patch provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54998 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-16T14:10:05.869Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54998","vendor":"Microsoft"}]
Threat ID: 6a46e7f427e9c797193afcb7
Added to database: 07/02/2026, 22:36:36 UTC
Last enriched: 07/02/2026, 22:51:19 UTC
Last updated: 07/02/2026, 22:51:38 UTC
Views: 3
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