What’s Vulnerable › Vulnerabilities

CVE-2026-35601: Vikunja has an iCalendar Property Injection via CRLF in CalDAV Task Output

• Severity: medium (CVSS 4.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-10 · updated 2026-10-26
• Weakness: CWE-93

Description

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the CalDAV output generator builds iCalendar VTODO entries via raw string concatenation without applying RFC 5545 TEXT value escaping. User-controlled task titles containing CRLF characters break the iCalendar property boundary, allowing injection of arbitrary iCalendar properties such as ATTACH, VALARM, or ORGANIZER. This vulnerability is fixed in 2.3.0.

Affected products

• go-vikunja vikunja: before 2.3.0 — fixed in 2.3.0

How to fix

Upgrade to a fixed version: go-vikunja vikunja 2.3.0. Check the vendor advisory for mitigations.

References

• https://github.com/go-vikunja/vikunja/pull/2580
• https://github.com/go-vikunja/vikunja/releases/tag/v2.3.0
• https://github.com/go-vikunja/vikunja/security/advisories/GHSA-2g7h-7rqr-9p4r
• https://github.com/go-vikunja/vikunja/security/advisories/GHSA-2g7h-7rqr-9p4r

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