CVE-2026-72798 is a high-severity (CVSS 8.6) CWE-862 vulnerability in github.com/siyuan-note/siyuan/kernel. O3 Security confirms whether CVE-2026-72798 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SiYuan: Publish-access filter on renderAttributeView leaves related-database content unfiltered and fails open on non-block first columns
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-2026-72798 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-2026-72798.
Summary
renderAttributeView correctly applies the reader publish-access filter, but the filter's row-accessibility decision is keyed solely to the row's first cell, and it never inspects the remaining cells' values. Relation and Rollup cells carry mirrored content from a different database, so a row belonging to a published database can hand an anonymous reader the contents of a related database whose host document is hidden, publish-forbidden, or password-protected. Separately, when the first column is not a block value the accessibility check is skipped entirely and the row is returned unchecked.
Note:
This is distinct from the previously reported password-tier omission in the same function that concerns the row's own primary block, whereas these two defects concern (a) other cells' related-database content, which no row-level check covers and (b) rows where the first cell is not a block at all. A fix to the row-drop condition alone would close neither.
Details
renderAttributeView applies the filter (kernel/api/av.go:68):
retDataMap["view"] = model.FilterViewByPublishAccess(c, publishAccess, retDataMap["view"].(av.Viewable))
Inside FilterViewByPublishAccess (kernel/model/publish_access.go):
if row.Cells[0].Value.Block != nil {
bt = treenode.GetBlockTree(row.Cells[0].Value.Block.ID)
}
if bt != nil {
if !CheckPathAccessableByPublishIgnore(bt.BoxID, bt.Path, publishIgnore) {
row = nil // drop
}
}
// every other cell in the row is returned as-is
(a) Relation and Rollup cells leak the related database. These value types carry mirrored content, not just references:
type ValueRelation struct { BlockIDs []string; Contents []*Value }
type ValueRollup struct { Contents []*Value }
The render pipeline populates them from a different attribute view e.g. kernel/model/attribute_view.go:2731:
v.GroupVal.Relation.Contents = []*av.Value{ relationDestAv.GetBlockValue(groupValue) }
relationDestAv is a separate database that may live in a hidden, publish-forbidden, or password-protected document. When a published database's row survives the filter (because its column-0 document is public), its Relation and Rollup columns return the related, non-published database's content block text, titles, and mirrored column values. FilterViewByPublishAccess performs no publish-access evaluation on Relation.Contents or Rollup.Contents.
(b) Fail-open when column 0 is not a block. bt is assigned only when row.Cells[0].Value.Block != nil. If the first column is a non-block type (Relation, Text, …) or the row is detached, bt remains nil, the if bt != nil guard is skipped, and the row is returned with no accessibility check at all. Column order is user-reorderable, so any database whose first column is not the document block bypasses row filtering entirely.
Verified at origin/master (eef105683).
Proof of Concept
Precondition: publish mode enabled (default port 6808); anonymous when Publish.Auth.Enable is false. Two databases: DB-A hosted in a published document, DB-B hosted in a publish-forbidden or password-protected document, with a Relation column in DB-A pointing at DB-B and containing a distinctive marker value.
(a) Related-database content disclosure:
POST http://127.0.0.1:6808/api/av/renderAttributeView
{"id":"<DB_A_AV_ID>"}
Rows of DB-A are returned (correctly, since its host document is public), and their Relation/Rollup cell Contents include DB-B's block text and mirrored column values, despite DB-B's host document being excluded from publishing.
(b) Fail-open row: Reorder DB-A so its first column is a non-block type (or use a detached row), mark its host document publish-forbidden, and request the same endpoint the row is returned without any accessibility evaluation.
Verification status: both defects are confirmed by code inspection at origin/master. A live demonstration requires a build from HEAD with two linked databases; available on request.
Impact
An anonymous reader (publish mode with auth disabled) or any publish RoleReader can read content from databases whose host documents are hidden, publish-forbidden, or password-protected, by requesting a published database that relates to them. Because relation graphs are commonly used to link a public index to private detail records, this exposes exactly the data the publish boundary is meant to withhold. The fail-open path additionally returns rows with no accessibility check whenever the first column is not a block value, which is a user-controlled layout property. Confidentiality-only.
Suggested fix
In FilterViewByPublishAccess:
- For each retained row, evaluate every
Relation.ContentsandRollup.Contentsentry againstCheckBlockIdAccessableByPublishAccess(including the publish-password tier) and drop or mask entries that fail. - Fail closed: when
row.Cells[0]has no accessible block (Value.Block == nilorbt == nil), drop the row rather than returning it unchecked.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/siyuan-note/siyuan/kernel | all versions | 0.0.0-20260724121519-426991d155c0 |
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 0.0.0-20260724121519-426991d155c0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-72798 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-2026-72798 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-2026-72798. 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-2026-72798 in your dependencies?
O3 detects CVE-2026-72798 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.