Summary
SiYuan: Full-content disclosure of publish-disabled documents via getHeading*Transaction endpoints (publish mode): reader-reachable rendered DOM with no publish-access check
CVE: This vulnerability corresponds to CVE-2026-68587.
Three "heading transaction" endpoints /api/block/getHeadingDeleteTransaction, /api/block/getHeadingLevelTransaction, and /api/block/getHeadingInsertTransaction return the rendered block DOM of a heading and its subtree in the computed transaction payload, with no publish-access check. They are gated by CheckAuth only, so they are reachable by the publish RoleReader token, and by the anonymous account when Publish.Auth.Enable is false.
Despite their write-implying names, these endpoints perform no mutation on this path, they compute a transaction object and return it, and that object contains RenderNodeBlockDOM output. As a result, an anonymous reader who supplies a heading block ID can read the full rendered content of a document that has been explicitly marked publish-disabled by an administrator, content that the reader-facing /api/filetree/getDoc path correctly refuses to return.
Details
Route / auth tier. All three routes are registered CheckAuth-only (no CheckAdminRole). CheckAuth admits RoleReader, and the publish proxy forwards port-6808 traffic with a Reader JWT (anonymous account when publish auth is disabled). Anonymous/reader reachable.
No publish-access filter. GetHeadingDeleteTransaction / GetHeadingLevelTransaction / GetHeadingInsertTransaction load the heading's block tree and render its DOM into the returned transaction's operation data. None of the three invokes IsReadOnlyRoleContext / the publish-access filter that the reader-safe content path (getDoc) applies. The reader-facing content endpoints (getDoc, and the CheckAdminRole-gated getBlockDOM/getBlockKramdown) treat rendered block DOM as gated content; these three transaction endpoints return the same rendered DOM without that gate.
Write-implying name, read behavior. On this code path the endpoints only compute the transaction (e.g. the undoOperations a delete would produce) and return it; nothing is deleted or modified. The returned operation data includes the rendered HTML of the heading subtree. This mismatch, mutation-shaped name, content-returning behavior is why the gap is easy to miss.
Proof of Concept
Reproduced on a local instance (SiYuan running locally, publish mode enabled on port 6808, publish Basic Auth disabled). DOC is a document containing a heading HEADING whose body contains the unique marker UNIQUE_MARKER_99, and DOC is marked publish-disabled by the administrator.
1. Confirm the document is publish-disabled (admin action, the boundary that should block reads):
POST http://127.0.0.1:6806/api/filetree/setPublishAccess
Authorization: Token <admin-token>
{"id":"DOC","visible":false,"password":"","disable":true}
2. Baseline: the reader-safe content path correctly blocks it (anonymous, port 6808):
POST http://127.0.0.1:6808/api/filetree/getDoc
{"id":"DOC"}
Returns the blocked/placeholder response, the publish filter is applied, no content.
3. Disclosure: the transaction endpoint returns the content (anonymous, port 6808):
POST http://127.0.0.1:6808/api/block/getHeadingDeleteTransaction
{"id":"HEADING"}
Returns HTTP 200; data.undoOperations[].data contains the rendered HTML of the heading subtree, including the hidden body text UNIQUE_MARKER_99. Nothing is deleted, the endpoint only computes the transaction. This is the full content of a publish-disabled document returned to an anonymous reader.
4. Sibling endpoints: same disclosure, same input:
POST http://127.0.0.1:6808/api/block/getHeadingLevelTransaction
{"id":"HEADING","level":2}
POST http://127.0.0.1:6808/api/block/getHeadingInsertTransaction
{"id":"HEADING"}
Both return the rendered DOM of the heading subtree in their operation data.
Impact
An anonymous reader (publish mode with auth disabled) or any publish RoleReader who supplies a heading block ID can read the full rendered content of a publish-disabled document, defeating a boundary the administrator explicitly configured.
Precondition: the request requires the target heading's block ID. Block IDs are high-entropy and are not returned by this endpoint, so this endpoint alone does not permit untargeted enumeration of arbitrary documents. However, block/heading IDs for publish-disabled documents are obtainable from other CheckAuth-only endpoints that lack the publish-access filter (the publish-boundary handler set reported separately, e.g. getHeadingChildrenIDs). Chained with such an ID source, this yields end-to-end unauthenticated full-content disclosure of publish-disabled documents. Presented standalone, the attacker must already possess the heading ID.
Impact is confidentiality-only: these endpoints return content but do not (on this path) modify data. No admin role, CSRF token, or write permission is required. Encrypted notebooks are out of scope.
The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.
CVE-2026-68587 has a CVSS score of 8.6 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.0.0-20260721013353-69db783b782a); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Apply the same publish-access check the content path uses IsReadOnlyRoleContext / the publish-access filter used by getDoc to all three getHeading*Transaction handlers, or gate them behind CheckAdminRole consistent with getBlockDOM/getBlockKramdown. Any endpoint that returns rendered block DOM should enforce the same publish boundary as the primary content path.
Frequently Asked Questions
- What is CVE-2026-68587? CVE-2026-68587 is a high-severity missing authorization vulnerability in github.com/siyuan-note/siyuan/kernel (go), affecting versions < 0.0.0-20260721013353-69db783b782a. It is fixed in 0.0.0-20260721013353-69db783b782a. The application does not perform an authorization check before performing a sensitive operation.
- How severe is CVE-2026-68587? CVE-2026-68587 has a CVSS score of 8.6 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of github.com/siyuan-note/siyuan/kernel are affected by CVE-2026-68587? github.com/siyuan-note/siyuan/kernel (go) versions < 0.0.0-20260721013353-69db783b782a is affected.
- Is there a fix for CVE-2026-68587? Yes. CVE-2026-68587 is fixed in 0.0.0-20260721013353-69db783b782a. Upgrade to this version or later.
- Is CVE-2026-68587 exploitable, and should I be worried? Whether CVE-2026-68587 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-68587 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-68587? Upgrade
github.com/siyuan-note/siyuan/kernelto 0.0.0-20260721013353-69db783b782a or later.