CVE-2019-0557 Cross-site scripting in Microsoft SharePoint
An attacker can execute arbitrary scripts in a victim's browser via a crafted request to Microsoft SharePoint, potentially stealing data or session tokens.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2019-0557?
CVE-2019-0557 is a medium-severity cross-site scripting vulnerability in Microsoft Sharepoint Server, published on 8 Jan 2019. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
A cross-site-scripting (XSS) vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server, aka "Microsoft Office SharePoint XSS Vulnerability." This affects Microsoft SharePoint. This CVE ID is unique from CVE-2019-0556, CVE-2019-0558.
Weakness: CWE-79
Which versions are affected by CVE-2019-0557?
It affects 1 product.
Products include Microsoft Sharepoint Server.
How do I fix CVE-2019-0557?
No fix has been published for CVE-2019-0557 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2019-0557 being exploited?
There is no known exploitation of CVE-2019-0557 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Sharepoint Server
- CVE-2026-50522 Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
- CVE-2026-58644 Microsoft SharePoint Deserialization of Untrusted Data
- CVE-2026-20963 Microsoft SharePoint Deserialization of Untrusted Data
- CVE-2025-53770 Microsoft SharePoint Deserialization of Untrusted Data
- CVE-2023-29357 Microsoft SharePoint Server Privilege Escalation
Sources
Also known as GHSA-mq5f-wqwg-gp8m.