CVE-2026-100633 (GCVE-0-2026-100633)
Vulnerability from cvelistv5
Published
2026-09-26 13:23
Modified
2026-10-05 15:21
Severity ?
8.5 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
VLAI Severity ?
EPSS score ?
CWE
- CWE-863 - Incorrect Authorization
Summary
SiYuan is a self-hosted personal knowledge management system. In versions 3.8.0 through 3.8.3, the MCP file tool's sensitive-path guard (util.IsForbiddenAbsPath(), invoked from resolvePath()) is applied only to the allowed root of recursive operations and not to each resolved descendant path — an incomplete fix for GHSA-c8r8-95hg-mp34. An authenticated administrator using the in-app Agent or the external MCP server can therefore bypass the protected-workspace-file denylist: file.grep can return matching lines from non-hidden protected descendants (for example conf/conf.json, TLS keys, data/snippets/conf.json, data/templates/, data/.siyuan/publishAccess.json, notebook .siyuan internals, or the kernel log), file.copy can copy protected descendants to an ordinary path where file.read can then retrieve them, and unzip can overwrite protected descendants using ordinary, lexically contained ZIP member names. Because file.grep is globally classified as a safe action, it receives no per-call confirmation, and the confirmation cards for file.copy and unzip show only the allowed root arguments. This issue is fixed in version 3.8.4. Suggested title: SiYuan 3.8.0 through 3.8.3 Sensitive-Path Guard Bypass in Recursive MCP File Operations.
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| siyuan-note | siyuan |
Version: 3.8.0 ≤ |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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