CVE-2026-68585 Overview
CVE-2026-68585 is a missing authorization vulnerability [CWE-862] in SiYuan, a personal knowledge management application. Versions before v3.7.3 expose document metadata through the /api/block/getBlockInfo endpoint without enforcing publish-access controls. Anonymous readers, or holders of publish RoleReader tokens, can supply a block identifier to retrieve the title, notebook, path, root ID, and icon of documents that administrators explicitly marked as excluded from publishing. The endpoint returns root metadata for publish-forbidden documents, breaking the trust boundary that administrators rely on to restrict content exposure.
Critical Impact
Unauthenticated remote attackers can enumerate metadata of documents administrators marked as excluded from publishing, exposing organizational knowledge structures.
Affected Products
- SiYuan versions prior to v3.7.3
- SiYuan instances exposing the publish interface to anonymous readers
- SiYuan deployments issuing publish RoleReader tokens
Discovery Timeline
- 2026-08-03 - CVE-2026-68585 published to the National Vulnerability Database
- 2026-08-03 - Last updated in NVD database
Technical Details for CVE-2026-68585
Vulnerability Analysis
The vulnerability resides in SiYuan's publish subsystem. The /api/block/getBlockInfo endpoint accepts a block ID and returns metadata for the containing document root. In vulnerable versions, the handler skips the publish-access verification that other publish endpoints enforce. As a result, the endpoint returns metadata for documents administrators explicitly excluded from publishing.
The returned payload includes the document title, notebook name, hierarchical path, root ID, and icon. This metadata reveals the structure and naming of private knowledge bases even when the underlying content remains gated. Attackers can iterate over candidate block IDs to enumerate document trees that were intended to remain hidden from unauthenticated visitors and low-privilege token holders.
Root Cause
The root cause is a missing authorization check on the getBlockInfo handler within the publish access path. The endpoint reads document root metadata without consulting the publish-forbidden list. Neither anonymous access nor the publish RoleReader role should have visibility into excluded documents, but the handler treats block metadata as unrestricted.
Attack Vector
Exploitation requires no authentication and no user interaction. An attacker sends an HTTP request to /api/block/getBlockInfo with a valid block ID belonging to a publish-forbidden document. The server responds with the document's title, notebook, path, root ID, and icon. Block IDs are guessable or discoverable through references in publicly published content, enabling systematic enumeration of restricted documents.
See the GitHub Security Advisory and the VulnCheck Advisory for additional technical detail.
Detection Methods for CVE-2026-68585
Indicators of Compromise
- Requests to /api/block/getBlockInfo originating from unauthenticated sessions or publish RoleReader tokens
- High-volume, sequential access patterns against /api/block/getBlockInfo suggesting block ID enumeration
- Responses returning metadata for documents present in the publish-forbidden list
Detection Strategies
- Inspect SiYuan access logs for getBlockInfo calls that reference root IDs matching publish-excluded documents
- Correlate anonymous session IDs with the volume of distinct block IDs queried per minute
- Alert on getBlockInfo requests from source IPs that never authenticate to the publish interface
Monitoring Recommendations
- Forward SiYuan publish gateway logs to a centralized logging platform for retention and query
- Baseline normal request rates against /api/block/ endpoints and alert on deviations
- Track publish RoleReader token issuance and revoke tokens issued before upgrading to v3.7.3
How to Mitigate CVE-2026-68585
Immediate Actions Required
- Upgrade SiYuan to v3.7.3 or later on all instances exposing the publish interface
- Audit the publish-forbidden document list and rotate any block IDs previously exposed to unauthenticated visitors
- Revoke and reissue outstanding publish RoleReader tokens after patching
Patch Information
SiYuan v3.7.3 adds the missing publish-access check to the /api/block/getBlockInfo handler. The patched handler consults the publish-forbidden list before returning root metadata and rejects requests for excluded documents. Refer to the GitHub Security Advisory GHSA-pm3w-vxp9-ccwc for release details.
Workarounds
- Restrict network access to the SiYuan publish interface behind an authenticated reverse proxy until the patch is applied
- Block anonymous access at the ingress layer and require authentication for all /api/block/ requests
- Remove or reclassify sensitive documents from publish-enabled notebooks until the upgrade completes
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
