CVE-2026-40922
SiYuan: Incomplete sanitization of bazaar README allows stored XSS via iframe srcdoc (incomplete fix for CVE-2026-33066)
Description
SiYuan is an open-source personal knowledge management system. In versions 3.6.1 through 3.6.3, a prior fix for XSS in bazaar README rendering (incomplete fix for CVE-2026-33066) enabled the Lute HTML sanitizer, but the sanitizer does not block iframe tags, and its URL-prefix blocklist does not effectively filter srcdoc attributes which contain raw HTML rather than URLs. A malicious bazaar package author can include an iframe with a srcdoc attribute containing embedded scripts in their README. When other users view the package in SiYuan's marketplace UI, the payload executes in the Electron context with full application privileges, enabling arbitrary code execution on the user's machine. This issue has been fixed in version 3.6.4.
INFO
Published Date :
April 17, 2026, 1:17 a.m.
Last Modified :
April 20, 2026, 4:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update SiYuan to version 3.6.4 or later.
- Avoid installing packages from untrusted sources.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40922.
| URL | Resource |
|---|---|
| https://github.com/advisories/GHSA-4663-4mpg-879v | Third Party Advisory |
| https://github.com/siyuan-note/siyuan/commit/b382f50e1880ed996364509de5a10a72d7409428 | Patch |
| https://github.com/siyuan-note/siyuan/releases/tag/v3.6.4 | Release Notes |
| https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8q5w-mmxf-48jg | Exploit Third Party Advisory |
| https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8q5w-mmxf-48jg | Exploit Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40922 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40922
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40922 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40922 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 20, 2026
Action Type Old Value New Value Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8q5w-mmxf-48jg -
Initial Analysis by [email protected]
Apr. 20, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:* versions from (including) 3.6.1 up to (excluding) 3.6.4 Added Reference Type GitHub, Inc.: https://github.com/advisories/GHSA-4663-4mpg-879v Types: Third Party Advisory Added Reference Type GitHub, Inc.: https://github.com/siyuan-note/siyuan/commit/b382f50e1880ed996364509de5a10a72d7409428 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/siyuan-note/siyuan/releases/tag/v3.6.4 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8q5w-mmxf-48jg Types: Exploit, Third Party Advisory -
New CVE Received by [email protected]
Apr. 17, 2026
Action Type Old Value New Value Added Description SiYuan is an open-source personal knowledge management system. In versions 3.6.1 through 3.6.3, a prior fix for XSS in bazaar README rendering (incomplete fix for CVE-2026-33066) enabled the Lute HTML sanitizer, but the sanitizer does not block iframe tags, and its URL-prefix blocklist does not effectively filter srcdoc attributes which contain raw HTML rather than URLs. A malicious bazaar package author can include an iframe with a srcdoc attribute containing embedded scripts in their README. When other users view the package in SiYuan's marketplace UI, the payload executes in the Electron context with full application privileges, enabling arbitrary code execution on the user's machine. This issue has been fixed in version 3.6.4. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/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 Added CWE CWE-79 Added Reference https://github.com/advisories/GHSA-4663-4mpg-879v Added Reference https://github.com/siyuan-note/siyuan/commit/b382f50e1880ed996364509de5a10a72d7409428 Added Reference https://github.com/siyuan-note/siyuan/releases/tag/v3.6.4 Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8q5w-mmxf-48jg