What is CVE-2026-23852?

CVE-2026-23852 is a critical-severity vulnerability in B3log Siyuan, classified under Code Injection. CVSS score: 9.6/10. Published 2026-01-19.

How severe is CVE-2026-23852?

Critical severity. CVSS v3 base score is 9.6 out of 10.

RCE in B3log Siyuan

CVE-2026-23852

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…

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.007 (47.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.

Affected products

B3log Siyuan
Siyuan-note Siyuan — versions < 3.5.4

Weakness classification (CWE)

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Patch, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-23852?: CVE-2026-23852 is a critical-severity vulnerability in B3log Siyuan, classified under Code Injection. CVSS score: 9.6/10. Published 2026-01-19.
How severe is CVE-2026-23852?: Critical severity. CVSS v3 base score is 9.6 out of 10.