CVE-2026-72804 is a high-severity (CVSS 8.6) Information Exposure vulnerability in github.com/siyuan-note/siyuan/kernel. O3 Security confirms whether CVE-2026-72804 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SiYuan: Graph endpoints omit the publish-password tier: anonymous readers receive block-level content of password-protected documents
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-72804.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-72804 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 371,256 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/siyuan-note/siyuan/kernelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
CVE: This vulnerability corresponds to CVE-2026-72804.
Summary
getGraph and getLocalGraph filter reader sessions against the visibility tier only and never check the publish password. Password-protected documents are Visible = true, so their graph nodes survive the filter and graph nodes are block-level and carry the block's actual content. An anonymous reader who has never supplied a document's password can therefore retrieve that document's per-block content and its reference/backlink topology. Both endpoints are CheckAuth-only, so they are reachable by the publish RoleReader token and by the anonymous account when Publish.Auth.Enable is false.
Details
Both handlers filter with the invisible-tier set only:
publishIgnore := model.GetInvisiblePublishAccess(publishAccess) // Visible tier ONLY
nodes, links = model.FilterGraphByPublishIgnore(publishIgnore, nodes, links)
FilterGraphByPublishIgnore (kernel/model/publish_access.go:849) drops a node only when !CheckPathAccessableByPublishIgnore(node.Box, node.Path, publishIgnore). There is no password evaluation anywhere in the graph code grepping graph.go for CheckPublishAuthCookie or password returns nothing.
Because password-protected documents are Visible = true, their nodes pass the filter unchanged.
The nodes carry content, not just titles. genTreeNodes emits one node per block, and nodeTitleLabel sets node.Title = node.Label = block.Content (kernel/model/graph.go:673-678). So each surviving node exposes the block's text.
This is materially broader than the by-design listing behaviour: listDocsByPath intentionally exposes protected document titles (protected means "publicly visible, password required to access"), but the graph endpoints expose per-block content and the full link/reference topology, which listing never does.
Verified at origin/master: FilterGraphByPublishIgnore contains only the CheckPathAccessableByPublishIgnore call; graph.go contains no password check; both routes are registered CheckAuth without CheckAdminRole.
Proof of Concept
Precondition: publish mode enabled (default port 6808); anonymous when Publish.Auth.Enable is false, otherwise any publish reader account. A document is marked protected (visible, password set) and contains blocks with distinctive content. No password is supplied in any request below.
Targeted: one protected document's content and reference structure:
POST http://127.0.0.1:6808/api/graph/getLocalGraph
{"id":"<PROTECTED_DOC_ID>"}
Returns nodes whose Title/Label contain the protected document's per-block content, plus its links/backlinks.
Workspace-wide: every protected document:
POST http://127.0.0.1:6808/api/graph/getGraph
{}
Returns block-level nodes for every protected document in the workspace, together with the complete link graph.
Control: requesting the same document through the normal content path returns the password placeholder confirming the password gate is enforced elsewhere and omitted here.
Impact
An anonymous reader (publish mode with auth disabled) or any publish RoleReader can read the block-level content of every password-protected document in the workspace, plus the full reference/backlink topology, without ever supplying a password. This defeats the publish-password control for the graph subsystem. Confidentiality-only, no modification.
Suggested fix
Extend the graph filter to evaluate the password tier in addition to visibility: in FilterGraphByPublishIgnore, drop a node unless the document's publish password is unset or the caller presents a valid publish-auth cookie for it (password == "" || CheckPublishAuthCookie(...)), matching the sibling filters that enforce both tiers. Consider also excluding block content from node Title/Label for reader sessions, so the graph conveys structure without document text.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/siyuan-note/siyuan/kernel | all versions | 0.0.0-20260724091654-82e9ded423e4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/siyuan-note/siyuan/kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/siyuan-note/siyuan/kernel to 0.0.0-20260724091654-82e9ded423e4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-72804 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-72804 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-72804. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-72804 in your dependencies?
O3 detects CVE-2026-72804 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.