CVE-2026-23852
SiYuan vulnerable to Stored XSS / RCE via `setBlockAttrs` icon attribute
SiYuan is a personal knowledge management system. Versions prior to 3.5.4 have a stored Cross-Site Scripting (XSS) vulnerability that allows an attacker to inject arbitrary HTML attributes into the icon attribute of a block via the /api/attr/setBlockAttrs API. The payload is later rendered in the dynamic icon feature in an unsanitized context, leading to stored XSS and, in the desktop environment, potential remote code execution (RCE). This issue bypasses the previous fix for issue #15970 (XSS → RCE via dynamic icons). Version 3.5.4 contains an updated fix.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.8
SiYuan vulnerable to Stored XSS / RCE via `setBlockAttrs` icon attribute
SiYuan is a personal knowledge management system. Versions prior to 3.5.4 have a stored Cross-Site Scripting (XSS) vulnerability that allows an attacker to inject arbitrary HTML attributes into the icon attribute of a block via the /api/attr/setBlockAttrs API. The payload is later rendered in the dynamic icon feature in an unsanitized context, leading to stored XSS and, in the desktop environment, potential remote code execution (RCE). This issue bypasses the previous fix for issue #15970 (XSS → RCE via dynamic icons). Version 3.5.4 contains an updated fix.
- Record
CVE-2026-23852- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:P - Weakness
- CWE-94
- Updated
- 2026-11-02
EUVDEUVD-2026-3290
5.8
SiYuan is a personal knowledge management system. Versions prior to 3.5.4 have a stored Cross-Site Scripting (XSS) vulnerability that allows an attacker to inject arbitrary HTML attributes into the icon attribute of a block via the /api/attr/setBlockAttrs API. The payload is later rendered in the dynamic icon feature in an unsanitized context, leading to stored XSS and, in the desktop environment, potential remote code execution (RCE). This issue bypasses the previous fix for issue #15970 (XSS → RCE via dynamic icons). Version 3.5.4 contains an updated fix.
- Record
EUVD-2026-3290- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:P - Updated
- 2026-11-02
NVD
5.8
SiYuan is a personal knowledge management system. Versions prior to 3.5.4 have a stored Cross-Site Scripting (XSS) vulnerability that allows an attacker to inject arbitrary HTML attributes into the icon attribute of a block via the /api/attr/setBlockAttrs API. The payload is later rendered in the dynamic icon feature in an unsanitized context, leading to stored XSS and, in the desktop environment, potential remote code execution (RCE). This issue bypasses the previous fix for issue #15970 (XSS → RCE via dynamic icons). Version 3.5.4 contains an updated fix.
- Record
CVE-2026-23852- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:P/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
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - Weakness
- CWE-94, CWE-79
- Updated
- 2026-11-02
OSV
5.8
SiYuan vulnerable to Stored XSS / RCE via `setBlockAttrs` icon attribute
SiYuan is a personal knowledge management system. Versions prior to 3.5.4 have a stored Cross-Site Scripting (XSS) vulnerability that allows an attacker to inject arbitrary HTML attributes into the icon attribute of a block via the /api/attr/setBlockAttrs API. The payload is later rendered in the dynamic icon feature in an unsanitized context, leading to stored XSS and, in the desktop environment, potential remote code execution (RCE). This issue bypasses the previous fix for issue #15970 (XSS → RCE via dynamic icons). Version 3.5.4 contains an updated fix.
- Record
CVE-2026-23852- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:P - Weakness
- CWE-94
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-23852 is a medium vulnerability (CVSS 5.8) in B3log Siyuan, published January 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.81%, the 57th percentile. No source names a fixed version.