CVE-2026-68586
published 2026-08-03CVE-2026-68586: SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and…
PriorityP348high8.6CVSS 3.1
AVNACLPRNUINSCCHINAN
EPSS
0.24%
15.6th percentile
SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and /api/ref/getBackmentionDoc). While the corresponding backlink list endpoints filter publish-forbidden documents, the content endpoints (gated only by CheckAuth) do not. A publish-mode reader — including an anonymous reader when publish Basic Auth is disabled — can call these endpoints directly with a publish-forbidden document's ID to retrieve its rendered DOM content and to determine whether the document references a given block (a reference-existence oracle).
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | siyuan-note_siyuan_kernel | >= 0 < 0.0.0-20260721014413-f45749a7ef6e | 0.0.0-20260721014413-f45749a7ef6e |
| siyuan-note | siyuan | < 3.7.3 | 3.7.3 |
CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
nvdv4.09.2CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/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
ghsa8.6HIGH
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
SiYuan: Cross-boundary content disclosure via getBacklinkDoc/getBackmentionDoc (publish mode): reader-reachable rendered DOM of publish-forbidden docs; sibling list endpoints are filtered
ghsa·2026-09-03·CVSS 8.6
CVE-2026-68586 [HIGH] CWE-862 SiYuan: Cross-boundary content disclosure via getBacklinkDoc/getBackmentionDoc (publish mode): reader-reachable rendered DOM of publish-forbidden docs; sibling list endpoints are filtered
SiYuan: Cross-boundary content disclosure via getBacklinkDoc/getBackmentionDoc (publish mode): reader-reachable rendered DOM of publish-forbidden docs; sibling list endpoints are filtered
**CVE:** This vulnerability corresponds to [CVE-2026-68586](https://nvd.nist.gov/vuln/detail/CVE-2026-68586).
### Summary
The backlink API splits into list endpoints (which documents reference a block) and content endpoints (the rendered text of those referencing blocks). The list endpoints apply a publish-access filter, the content endpoints do not. As a result, `/api/ref/getBacklinkDoc` and `/api/ref/getBackmentionDoc` return the rendered DOM of blocks belonging to a publish-forbidden document to an anonymous reader, with no access check.
Both content endpoints are gated by `CheckAuth` only, reachab
GHSA
SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and /api/ref/getBackmentionDoc).
ghsa_unreviewed·2026-08-03
CVE-2026-68586 [CRITICAL] CWE-862 SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and /api/ref/getBackmentionDoc).
SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and /api/ref/getBackmentionDoc). While the corresponding backlink list endpoints filter publish-forbidden documents, the content endpoints (gated only by CheckAuth) do not. A publish-mode reader — including an anonymous reader when publish Basic Auth is disabled — can call these endpoints directly with a publish-forbidden document's ID to retrieve its rendered DOM content and to determine whether the document references a given block (a reference-existence oracle).
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-08-03
Published