CVE-2026-87814
SiYuan before v3.8.2 Stored XSS via Asset Preview
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Active
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
8.4
SiYuan before v3.8.2 Stored XSS via Asset Preview
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
- Record
CVE-2026-87814- CVSS 4.0
- 8.4 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-74840
8.4
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
- Record
EUVD-2026-74840- CVSS 4.0
- 8.4 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-gxwj-6x5p-v77c
8.4
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset...
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
- Record
GHSA-gxwj-6x5p-v77c- CVSS 4.0
- 8.4 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/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
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
8.4
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
- Record
CVE-2026-87814- CVSS 4.0
- 8.4 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/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
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
8.4
SiYuan before v3.8.2 Stored XSS via Asset Preview
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
- Record
CVE-2026-87814- CVSS 4.0
- 8.4 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-87814 is a high vulnerability (CVSS 8.4) in Siyuan-note Siyuan, published September 9, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.37%, the 30th percentile. No source names a fixed version.