Details
### Summary
`/api/block/getRefIDs` filters its results for reader roles through a helper that checks only the visibility tiers. The password tier is not checked, because the helper does not receive the request context and therefore cannot evaluate the publish auth cookie. A reader who has not entered a document's publish password learns that the document references a given block.
A function ten lines away in the same file does perform the full check, on the same input type.
### Details
**Route,** identical at `eef105683` (`kernel/api/router.go:235`) and dev `a7ae96ce` (`:245`):
```go
ginServer.Handle("POST", "/api/block/getRefIDs", model.CheckAuth, getRefIDs)
```
No `CheckReadonly`, no `CheckAdminRole`.
**The filter chain.** `getRefIDs` (`kernel/api/block.go:631`) checks `isEncryptedNotebookDeniedForPublish`, calls `model.GetBlockRefsInBox`, then for read-only roles:
```go
publishIgnore := model.GetInvisiblePublishAccess(publishAccess)
refDefs, originalRefBlockIDs = model.FilterRefDefsByPublishIgnore(publishIgnore, refDefs)
```
`FilterRefDefsByPublishIgnore` (`kernel/model/publish_access.go:1324`) collects the reference and definition identifiers, resolves their block trees, and delegates the decision to `FilterBlockTreesByPublishIgnore` (`:1314`), whose entire body is:
```go
for id, bt := range bts {
if CheckPathAccessableByPublishIgnore(bt.BoxID, bt.Path, publishIgnore) {
ret[id] = bt
}
}
```
Inside that helper, `CheckPublishAuthCookie`, `GetPathPasswordByPublishAccess`, `checkBlockTreeAccessableByPublishAccess` and `password` all appear zero times.
**The complete check exists in the same file.** `kernel/model/publish_access.go:431`:
```go
func checkBlockTreeAccessableByPublishAccess(c *gin.Context, publishAccess PublishAccess, bt *treenode.BlockTree) bool {
if bt == nil || IsEncryptedBoxDeniedByPublishAccess(bt.BoxID) {
return false
}
publishIgnore := filterDisablePublishAccess(publishAccess)
passwordID, password := GetPathPasswordByPublishAccess(bt.BoxID, bt.Path, publishAccess)
return CheckPathAccessableByPublishIgnore(bt.BoxID, bt.Path, publishIgnore) &&
(password == "" || CheckPublishAuthCookie(c, passwordID, password))
}
```
Same package, same file, same `*treenode.BlockTree` input. One takes the context and evaluates the password; the other does not receive it and structurally cannot.
**Route-level contrast.** The adjacent `getChildBlocks` and `getTailChildBlocks` both carry `model.CheckAdminRole`.
**Note on a prior assessment.** `getRefIDs` has been described as correctly filtered because it calls a publish-access filter. It does. The filter it calls covers the visibility tiers only.
### Proof of Concept
Kernel 3.7.2, publish mode on port 6808, `Publish.Auth.Enable` false, anonymous client. A public document referenced from a second document whose publish tier was changed between runs. `getRefIDs` was called anonymously each time.
| Tier of the referring document | Anonymous result |
|---|---|
| Public | reference returned (baseline) |
| Password-protected | **reference still returned** |
| Hidden | `[]`, filtered |
| Forbidden | `[]`, filtered |
The hidden and forbidden rows confirm the filter runs and works. The password-protected row is the defect.
### Impact
An anonymous reader in publish mode, or any publish `RoleReader`, learns that a password-protected document contains a reference to a given block, without entering that document's password, and receives the block identifiers involved.
Scoped precisely: the response carries identifiers only. `type RefDefs { RefID string; DefIDs []string }`, returned alongside `originalRefBlockIDs`, a map of identifier to identifier. There is no reference text, title or content. The disclosure is the existence of a relationship, plus identifiers usable as input to other endpoints.
Confidentiality only.
### Suggested fix
Thread `*gin.Context` into `FilterRefDefsByPublishIgnore` and `FilterBlockTreesByPublishIgnore`, and use `checkBlockTreeAccessableByPublishAccess` in place of the bare `CheckPathAccessableByPublishIgnore` call, so the password tier and the encrypted-box check are both applied.
EPSS, exploit probability
Low0.33%
estimated chance of real-world exploitation in the next 30 days, higher than 23.2% of every CVE FIRST.org scores
Refreshed 10/1/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.
