Microsoft Exchange Server Elevation of Privilege Vulnerability
Published June 9, 2026Updated June 23, 2026
Source data
Overview
Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
Impact & technical details
Elevation of Privilege
What privileges could be gained by an attacker who successfully exploited the vulnerability? An attacker could gain elevated privileges beyond those normally available to them, allowing actions such as accessing restricted information or performing operations that are typically limited to more highly privileged users or administrators.
How could an attacker exploit this vulnerability? An attacker with a low-privilege user account and an assigned mailbox, could exploit weaknesses in how Exchange validates requests and identity tokens to impersonate another user. By doing so, the attacker could then access mailboxes through Exchange services as if they were that user.
- CVSS base score
- 8.8 / 10
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Highest base score supplied by MSRC for this record; the vector belongs to that score. Ratings can vary by product. Microsoft Important is displayed as High; Moderate is displayed as Medium.
Affected products
- Microsoft Exchange Server 2016 Cumulative Update 23
- Microsoft Exchange Server 2019 Cumulative Update 14
- Microsoft Exchange Server 2019 Cumulative Update 15
- Microsoft Exchange Server Subscription Edition RTM
Source guidance
Remediation
The source provides update references without a separate remediation summary. Review the applicable update links below.
At least one Microsoft vendor-fix reference is available. Check each affected product for its applicable update, prerequisites, and supported version.
GTP recommendation · Rule-based guidance
Recommended next step
Review affected Microsoft products and apply the applicable security updates through your organization's normal patch-management process. Confirm availability and prerequisites in the Microsoft advisory.
Authoritative sources & updates
Findings and update information come from the linked publishers. GTP compiles the public record and provides the recommendation above. CVSS ratings shown here come from Microsoft. NVD references provide additional public context.
- Microsoft Security Response Center (opens in a new tab)
- Microsoft security update · 5103212 (opens in a new tab)
- Microsoft remediation guidance (opens in a new tab)
- Microsoft remediation guidance (opens in a new tab)
- Microsoft remediation guidance (opens in a new tab)
- Microsoft remediation guidance (opens in a new tab)
Managed by GTP?
Griffin Technology Partners managed customers may receive additional environment-specific security guidance and remediation assistance through their managed services relationship.
Security bulletins are provided for informational purposes and compiled from authoritative public sources. Vulnerability applicability varies by environment. Validate affected products, configuration, compatibility requirements, and vendor guidance before making production changes.