Executive brief
SiYuan is a personal knowledge management system and note-taking application. A security flaw allows an unauthenticated attacker to remotely access and download the entire contents of a user's database, including private notes, tags, and attachments. This could lead to a total loss of data privacy for users hosting their notes on a network-accessible server.
Technical details
The `/api/icon/getDynamicIcon` endpoint in SiYuan's kernel router is explicitly configured to bypass authentication. When the `type` parameter is set to 8, the endpoint utilizes `RenderDynamicIconContentTemplate` to process the `content` parameter as a Go template. This template engine has access to `querySQL` and `queryBlocks` functions, which can execute arbitrary SELECT statements against the underlying SQLite database. An attacker who knows or discovers a valid 22-character block ID (often leaked in shared URLs or browser history) can use this injection to exfiltrate all note content, metadata, and attributes. The vulnerability was patched in a June 2026 kernel update.
Affected products
- siyuan-note SiYuan < 0.0.0-20260628153353-2d5d72223df4
Timeline
- 2026-06-24: disclosed: NVD publication date
- 2026-06-28: patched: First patched version released
- 2026-07-10: advisory: GitHub Advisory published