# CVE-2026-45479: Microsoft Office SharePoint Cross-Site Scripting

Source: https://junglewise.ai/threats/cve-2026-45479-microsoft-office-sharepoint-cross-site-scripting  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-09. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-45479 · Severity: medium · CVSS 4.6 · Published 2026-06-09

Microsoft Office SharePoint, a widely used platform for document management and team collaboration, is affected by a security vulnerability that could allow an attacker to perform spoofing attacks. By tricking a user into interacting with a malicious link or page, an attacker with basic user permissions could execute unauthorized scripts in the victim's browser. This could lead to the unauthorized access of sensitive information or the performance of actions on behalf of the user within the SharePoint environment.

Technologies: [Microsoft SharePoint](https://junglewise.ai/threats/technologies/sharepoint). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-45479 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-45479 being exploited in the wild.

**How severe is CVE-2026-45479?** Medium severity, with a CVSS score of 4.6, published 9 June 2026.

**Which products and versions are affected?** Microsoft Office SharePoint.

**Is there a fix for CVE-2026-45479?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-45479 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-45479?** Check whether you run Microsoft SharePoint. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stored or reflected cross-site scripting (XSS) vulnerability exists in Microsoft Office SharePoint due to improper neutralization of user-supplied input during web page generation. An attacker with low-level authenticated permissions (PR:L) can exploit this over the network by injecting malicious scripts. Successful exploitation requires a legitimate user to interact with a crafted link or page (UI:R). This allows the attacker to execute arbitrary script code in the context of the victim's browser session, potentially leading to session hijacking or unauthorized data disclosure. Microsoft has released security updates to address this issue via the MSRC update guide.

## Affected products

- Microsoft Office SharePoint

## Timeline

- 2026-06-09: advisory: Initial disclosure by Microsoft and NVD.

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45479](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45479)

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