Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, TaskAttachment.ReadOne() queries attachments by ID only (WHERE id = ?), ignoring the task ID from the URL path. The permission check in CanRead() validates access to the task specified in the URL, but ReadOne() loads a different attachment that may belong to a task in another project. This allows any authenticated user to download or delete any attachment in the system by providing their own accessible task ID with a target attachment ID. Attachment IDs are sequential integers, making enumeration trivial. Version 2.2.1 patches the issue.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-639"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33678.json"
}{
"cpe": "cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "2.2.1"
}
],
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
]
}