Vulnerability · Published Feb 25, 2026 · Assigned by GitHub_M

CVE-2026-27616Vikunja Vulnerable to Stored Cross-Site Scripting (XSS) via Unsanitized SVG Attachment Upload Leading to Token Exposure

High 7.3

In plain English

A high-severity cross-site scripting in vikunja from go-vikunja. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).

Severity (CVSS 3.1)7.3High

Exploit odds (30 days)0.5%top 56.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Vikunja is an open-source self-hosted task management platform. Prior to version 2.0.0, the application allows users to upload SVG files as task attachments. SVG is an XML-based format that supports JavaScript execution through elements such as <script> tags or event handlers like onload. The application does not sanitize SVG content before storing it. When the uploaded SVG file is accessed via its direct URL, it is rendered inline in the browser under the application's origin. As a result, embedded JavaScript executes in the context of the authenticated user. Because the authentication token is stored in localStorage, it is accessible via JavaScript and can be retrieved by a malicious payload. Version 2.0.0 patches this issue.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	code.vikunja.io/api	no fix listed	GHSA-7jp5-298q-jg98
Go	code.vikunja.io/api	no fix listed	GO-2026-4553

Affected products (as reported)

Vendor	Product	Versions
go-vikunja	vikunja	< 2.0.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

References

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-7jp5-298q-jg98 x_refsource_CONFIRM
https://github.com/user-attachments/files/25414870/Stored.XSS.Proof.of.concept.pdf x_refsource_MISC
https://vikunja.io/changelog/vikunja-v2.0.0-was-released x_refsource_MISC