SiYuan before v3.7.4 Path Traversal via getUniqueFilename

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

SiYuan versions before v3.7.4 contain a path traversal vulnerability in the getUniqueFilename endpoint that allows anonymous readers to probe filesystem existence without validation or confinement. Attackers can supply arbitrary absolute paths to determine whether files and directories exist on the host, enabling reconnaissance of the filesystem layout and installed software.

Source published

13 Aug 2026 11:28:10 UTC

Source modified

14 Aug 2026 20:18:37 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N

CVSS 3.1 · 5.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

SiYuan versions before v3.7.4 contain a path traversal vulnerability in the getUniqueFilename endpoint that allows anonymous readers to probe filesystem existence without validation or confinement. Attackers can supply arbitrary absolute paths to determine whether files and directories exist on the host, enabling reconnaissance of the filesystem layout and installed software.

Source published

13 Aug 2026 12:17:24 UTC

Source modified

24 Oct 2026 15:10:00 UTC

Observed here

25 Oct 2026 15:19:09 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS 3.1 · [email protected] · Secondary · 5.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

### Summary `/api/file/getUniqueFilename` takes a path from the request body and passes it to a filesystem existence check with no validation, confinement or authorization. The response distinguishes paths that exist from paths that do not, so an anonymous reader in publish mode can probe arbitrary locations on the host, one request per probe. Files and directories both work. Every neighbouring file route either requires an administrator or confines the path first. ### Details **Route.** `kernel/api/router.go:289` on master, `:292` on the development branch, `CheckAuth` only. **Handler,** `kernel/api/file.go:84`, in full: ```go util.ParseJsonArgs(arg, ret, util.BindJsonArg("path", &filePath, true, true)) ret.Data = map[string]any{"path": util.GetUniqueFilename(filePath)} ``` **The argument binder does no path handling.** `util.BindJsonArg` (`kernel/util/net.go:365`) takes two booleans, `required` (the key must be present) and `rejectEmpty` (the value must be non-empty). That is its entire contract. There is no `filepath.Clean`, no workspace join, no traversal check. An absolute path outside the workspace reaches `gulu.File.IsExist` unmodified. **The oracle.** `util/file.go:67`: ```go if !gulu.File.IsExist(filePath) { return filePath } // otherwise loop, returning the first non-existent dir/base (i).ext ``` Input echoed back means the path does not exist. A `(1)` suffix means it does. **The asymmetry.** | Route | Middleware | |---|---| | `putFile`, `copyFile`, `globalCopyFiles`, `workspaceCopyFiles`, `removeFile`, `renameFile` | `CheckAuth`, `CheckAdminRole`, `CheckReadonly` | | `readDir` (directory enumeration) | `CheckAuth`, `CheckAdminRole` | | `getFile` | `CheckAuth`, but `GetAbsPathInWorkspace` returns 403 on escape, plus `rejectEncryptedBoxPath` and a publish-access check | | `getUniqueFilename` | `CheckAuth`, nothing else | `getFile` binds the identical `BindJsonArg("path", &filePath, true, true)` and confines it as its first action. ### Proof of Concept Kernel 3.7.2, publish mode on port 6808, `Publish.Auth.Enable` false, anonymous client. Reader context confirmed by `getChildBlocks` returning HTTP 403 on the same session. ``` {"path":"/etc/passwd"} → {"code":0,"msg":"","data":{"path":"/etc/passwd (1)"}} {"path":"/etc/shadow"} → {"code":0,"msg":"","data":{"path":"/etc/shadow (1)"}} {"path":"/etc/definitely-not-here"} → {"code":0,"msg":"","data":{"path":"/etc/definitely-not-here"}} ``` Directories behave the same way: ``` {"path":"/root"} → {"path":"/root (1)"} {"path":"/rootnope"} → {"path":"/rootnope"} ``` And within the workspace, confirming whether a specific document file exists: ``` {"path":"<workspace>/data/<boxID>/<docID>.sy"} → "<...> (1).sy" {"path":"<workspace>/data/nope-no-such.sy"} → echoed unchanged ``` ### Impact An anonymous reader in publish mode, or any publish `RoleReader`, determines whether arbitrary paths exist on the host. Because directories respond the same way as files, the filesystem can be walked rather than only guessed at. This supports identifying the operating-system user's home directory, detecting installed software, backup and synchronisation directories, mapping the workspace layout, and confirming the existence of specific documents by probing their storage paths. It also composes with the absolute workspace path returned elsewhere, which supplies a concrete prefix rather than requiring guesswork, and it recovers the operating-system username that the browser-request path strip added under issue #17410 was introduced to conceal. Scoped precisely: nothing is read and nothing is written. This is an existence and layout disclosure, valuable primarily as a reconnaissance step. ### Suggested fix Confine the path as the adjacent `getFile` route does, by routing `filePath` through `util.GetAbsPathInWorkspace` and returning 403 on escape, or add `CheckAdminRole` and `CheckReadonly` to match `readDir`. The frontend uses this endpoint only for naming uploads and assets inside the workspace, so neither change affects legitimate use.

Source published

1 Oct 2026 15:46:01 UTC

Source modified

7 Oct 2026 17:55:29 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

Publisher rating · MODERATE

SiYuan: getUniqueFilename passes an unvalidated client-supplied path to the filesystem, giving anonymous readers an existence oracle over the entire host filesystem in github.com/siyuan-note/siyuan/kernel

Source published

7 Oct 2026 14:09:59 UTC

Source modified

7 Oct 2026 17:45:13 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.