CVE-2023-33159
Published: 11 July 2023
Summary
CVE-2023-33159 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Microsoft Sharepoint Server. Its CVSS base score is 8.8 (High).
Operationally, ranked at the 47.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
Deeper analysis
CVE-2023-33159 is a spoofing vulnerability affecting Microsoft SharePoint Server. It carries a CVSS 3.1 base score of 8.8 and is associated with CWE-79, indicating a cross-site scripting component that can be triggered over the network with low attack complexity.
An unauthenticated attacker can exploit the flaw by sending a crafted request that requires user interaction, such as clicking a link. Successful exploitation allows the attacker to spoof content and achieve high impact on confidentiality, integrity, and availability within the affected SharePoint deployment.
Microsoft has published guidance for the issue in its security update guide at the listed MSRC reference URL.
The EPSS score for this CVE rose materially from a low baseline to a peak of 0.0741 on 2025-01-22 before receding to its current value of 0.0024, indicating a period of increased exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-37344
Vulnerability details
Microsoft SharePoint Server Spoofing Vulnerability
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.