FlintSH Flare 1.7.1 SVG cross site scripting

Summaryinfo

A vulnerability was found in FlintSH Flare 1.7.1. It has been rated as problematic. This impacts an unknown function of the component SVG Handler. The manipulation leads to cross site scripting. This vulnerability is documented as CVE-2026-26993. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in FlintSH Flare 1.7.1 and classified as problematic. This issue affects an unknown function of the component SVG Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

Flare is a Next.js-based, self-hostable file sharing platform that integrates with screenshot tools. Versions 1.7.0 and below allow users to upload files without proper content validation or sanitization. By embedding malicious JavaScript within an SVG (or other active content formats such as HTML or XML), an attacker can achieve script execution in the context of the application's origin when a victim views the file in “raw” mode. This results in a stored Cross-Site Scripting (XSS) vulnerability that can be exploited to exfiltrate user data. This issue has been fixed in version 1.7.1.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-26993 since 02/17/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 1.7.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 7763d7b954799552f287ab9260bb1353f8880163 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• FlintSH

Name

• Flare

Version

• 1.7.1

License

• open-source

Website

• Product: https://github.com/FlintSH/Flare/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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