# CVE-2026-40259: SiYuan: Publish Reader Can Arbitrarily Delete Attribute View Files via removeUnusedAttributeView API > An authenticated reader can arbitrarily delete attribute view files in SiYuan, causing data loss and rendering breakage. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`) - **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-7m5h-w69j-qggg, GO-2026-5229 ## What is CVE-2026-40259? CVE-2026-40259 is a high-severity missing authorization 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 3.6.3 and below, the /api/av/removeUnusedAttributeView endpoint is protected only by generic authentication that accepts publish-service RoleReader tokens. The handler passes a caller-controlled id directly to a model function that unconditionally deletes the corresponding attribute view file from the workspace without verifying that the caller has write privileges or that the target attribute view is actually unused. An authenticated publish-service reader can permanently delete arbitrary attribute view definitions by extracting publicly exposed data-av-id values from published content, causing breakage of database views and workspace rendering until manually restored. This issue has been fixed in version 3.6.4. Weakness: CWE-285 (Improper Authorization) ## Which versions are affected by CVE-2026-40259? 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 | 0.0.0-20260407035653-2f416e5253f1 | | `github.com/siyuan-note/siyuan/kernel` | Go | All versions | 0.0.0-20260407035653-2f416e5253f1 | | `github.com/siyuan-note/siyuan/kernel` | Go | All versions | 0.0.0-20260407035653-2f416e5253f1 | Products: B3log Siyuan. ## How do I fix CVE-2026-40259? Upgrade github.com/siyuan-note/siyuan/kernel to 0.0.0-20260407035653-2f416e5253f1 or later. ## Is CVE-2026-40259 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40259 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-2026-40259 and fix it if it is affected. What it is: CVE-2026-40259 is a high-severity missing authorization 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-2026-40259 exists. Affected packages and fixed versions: - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260407035653-2f416e5253f1 - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260407035653-2f416e5253f1 - github.com/siyuan-note/siyuan/kernel (Go): affected all versions; fixed in 0.0.0-20260407035653-2f416e5253f1 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-2026-40259/ (Markdown: https://insights.sbomify.com/CVE-2026-40259/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40259 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40259 - OSV: https://osv.dev/vulnerability/CVE-2026-40259 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-40259/ Summaries are generated and may contain mistakes; the official description above is the record.