CVE-2026-45503: CWE-285: Improper Authorization in Microsoft Microsoft Exchange Server 2016 Cumulative Update 23
Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to disclose information over a network.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-45503) in Microsoft Exchange Server 2016 Cumulative Update 23 is classified as CWE-285 (Improper Authorization). It allows an attacker with some level of authorization to exploit server-side request forgery (SSRF) to disclose sensitive information over the network. The CVSS v3.1 base score is 8.1, indicating high severity, with network attack vector, low attack complexity, and no user interaction required. The integrity and confidentiality impacts are high, while availability is not affected. Microsoft has released an official fix for this vulnerability.
Potential Impact
An authorized attacker can exploit this SSRF vulnerability to disclose sensitive information over the network, potentially leading to information leakage that could aid further attacks. The confidentiality and integrity of the affected system are impacted, but availability is not affected. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. It is recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45503 to remediate this vulnerability.
CVE-2026-45503: CWE-285: Improper Authorization in Microsoft Microsoft Exchange Server 2016 Cumulative Update 23
Description
Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to disclose information over a network.
CVSS v3.1
Score 8.1high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-45503) in Microsoft Exchange Server 2016 Cumulative Update 23 is classified as CWE-285 (Improper Authorization). It allows an attacker with some level of authorization to exploit server-side request forgery (SSRF) to disclose sensitive information over the network. The CVSS v3.1 base score is 8.1, indicating high severity, with network attack vector, low attack complexity, and no user interaction required. The integrity and confidentiality impacts are high, while availability is not affected. Microsoft has released an official fix for this vulnerability.
Potential Impact
An authorized attacker can exploit this SSRF vulnerability to disclose sensitive information over the network, potentially leading to information leakage that could aid further attacks. The confidentiality and integrity of the affected system are impacted, but availability is not affected. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. It is recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45503 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-05-12T16:07:22.619Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45503","vendor":"Microsoft"}]
Threat ID: 6a284cdf8dd33fbd85664da9
Added to database: 6/9/2026, 5:26:55 PM
Last enriched: 6/9/2026, 10:10:54 PM
Last updated: 6/10/2026, 6:15:48 AM
Views: 5
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