CVE-2026-35602: Vikunja has a File Size Limit Bypass via Vikunja Import

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-10 · updated 2026-10-26
Weakness: CWE-770

Description

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the Vikunja file import endpoint uses the attacker-controlled Size field from the JSON metadata inside the import zip instead of the actual decompressed file content length for the file size enforcement check. By setting Size to 0 in the JSON while including large compressed file entries in the zip, an attacker bypasses the configured maximum file size limit. 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

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