# CVE-2026-55019: Microsoft SharePoint cross-site scripting spoofing vulnerability

Source: https://junglewise.ai/threats/cve-2026-55019-microsoft-sharepoint-cross-site-scripting-spoofing-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2026-55019 · Severity: medium · CVSS 4.6 · Published 2026-07-14

Microsoft SharePoint, a widely used collaboration and document management platform, is affected by a security vulnerability that could allow an attacker to impersonate legitimate users. By tricking a user into clicking a malicious link, an attacker with basic access to the network could execute unauthorized scripts in the victim's browser. This could lead to the theft of sensitive information or unauthorized actions performed on behalf of the user within the SharePoint environment.

Technologies: [Microsoft SharePoint Enterprise Server 2016](https://junglewise.ai/threats/technologies/sharepoint-enterprise-server-2016), [Microsoft SharePoint Server 2019](https://junglewise.ai/threats/technologies/sharepoint-server-2019), [Microsoft SharePoint Server Subscription Edition](https://junglewise.ai/threats/technologies/sharepoint-server-subscription-edition). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-55019 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55019 being exploited in the wild.

**How severe is CVE-2026-55019?** Medium severity, with a CVSS score of 4.6, published 14 July 2026.

**Which products and versions are affected?** Microsoft SharePoint Enterprise Server 2016 16.0.0 to 16.0.5561.1001; Microsoft SharePoint Server 2019 16.0.0 to 16.0.10417.20175; Microsoft SharePoint Server Subscription Edition 16.0.0 to 16.0.19725.20434.

**Is there a fix for CVE-2026-55019?** 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-2026-55019 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-55019?** Check whether you run Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019 or Microsoft SharePoint Server Subscription Edition at an affected version. 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 cross-site scripting (XSS) vulnerability exists in Microsoft SharePoint due to improper neutralization of input during web page generation. An authenticated attacker with low privileges can exploit this vulnerability by sending a specially crafted request to a target SharePoint server. Successful exploitation requires a victim to interact with a malicious link or page, allowing the attacker to execute arbitrary script in the context of the victim's browser. This can result in session hijacking, unauthorized data access, or spoofing. The vulnerability affects SharePoint Enterprise Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition.

## Affected products

- Microsoft SharePoint Enterprise Server 2016 16.0.0 to 16.0.5561.1001
- Microsoft SharePoint Server 2019 16.0.0 to 16.0.10417.20175
- Microsoft SharePoint Server Subscription Edition 16.0.0 to 16.0.19725.20434

## Timeline

- 2026-07-14: disclosed: Initial publication of the CVE record by Microsoft.
- 2026-07-14: advisory: Microsoft released the Security Update Guide for this vulnerability.

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55019](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55019)

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