# CVE-2026-40922: SiYuan has incomplete fix for CVE-2026-33066: XSS > A stored XSS vulnerability in SiYuan allows malicious bazaar package authors to execute arbitrary code on users' machines via iframe srcdoc payloads. - **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 16 Apr 2026 - **Updated:** 20 Apr 2026 - **Also known as:** GHSA-8q5w-mmxf-48jg, GO-2026-5260 ## What is CVE-2026-40922? CVE-2026-40922 is a medium-severity cross-site scripting vulnerability in B3log Siyuan, published on 16 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim. ### Official 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. Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation) ## Which versions are affected by CVE-2026-40922? 3 open source packages ship an affected version, including github.com/siyuan-note/siyuan/kernel. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/siyuan-note/siyuan/kernel` | Go | All versions | 0.0.0-20260414013942-62eed37a3263 | | `github.com/siyuan-note/siyuan/kernel` | Go | All versions | 0.0.0-20260414013942-62eed37a3263 | | `github.com/siyuan-note/siyuan/kernel` | Go | All versions | 0.0.0-20260414013942-62eed37a3263 | Products: B3log Siyuan. ## How do I fix CVE-2026-40922? Upgrade github.com/siyuan-note/siyuan/kernel to 0.0.0-20260414013942-62eed37a3263 or later. ## Is CVE-2026-40922 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40922 exists. ## Other vulnerabilities in B3log Siyuan - [CVE-2026-32938](https://insights.sbomify.com/CVE-2026-32938/): SiYuan has an Arbitrary File Read in its Desktop Publish Service (critical 9.9) - [CVE-2026-33669](https://insights.sbomify.com/CVE-2026-33669/): SiYuan has Arbitrary Document Reading within the Publishing Service (critical 9.8) - [CVE-2026-33670](https://insights.sbomify.com/CVE-2026-33670/): SiYuan has directory traversal within its publishing service (critical 9.8) - [CVE-2026-32767](https://insights.sbomify.com/CVE-2026-32767/): SiYuan: Authorization Bypass Allows Arbitrary SQL Execution via Search API (critical 9.8) - [CVE-2024-53504](https://insights.sbomify.com/CVE-2024-53504/): SQL injection in n/a (critical 9.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-40922 and fix it if it is affected. What it is: CVE-2026-40922 is a medium-severity cross-site scripting vulnerability in B3log Siyuan, published on 16 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40922 exists. Affected packages and fixed versions: - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260414013942-62eed37a3263 - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260414013942-62eed37a3263 - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260414013942-62eed37a3263 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-40922/ (Markdown: https://insights.sbomify.com/CVE-2026-40922/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40922 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40922 - OSV: https://osv.dev/vulnerability/CVE-2026-40922 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-40922/ Summaries are generated and may contain mistakes; the official description above is the record.