# CVE-2026-82649: SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path

> Local attackers can escalate privileges by placing malicious executables in the installer directory, exploiting uncontrolled search paths in the Windows installer.

- **Severity:** High 7.0 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 30 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-9j65-967f-5rv3, GHSA-jrgp-6vq3-j6hp

## What is CVE-2026-82649?

CVE-2026-82649 is a high-severity path traversal vulnerability in siyuan-note siyuan, published on 30 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation.

Weakness: CWE-427 (Uncontrolled Search Path Element)

## Which versions are affected by CVE-2026-82649?


## How do I fix CVE-2026-82649?

No fix has been published for CVE-2026-82649 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-82649 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82649 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82649 and fix it if it is affected.

What it is: CVE-2026-82649 is a high-severity path traversal vulnerability in siyuan-note siyuan, published on 30 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82649 exists.

Affected product: siyuan-note siyuan. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-82649/ (Markdown: https://insights.sbomify.com/CVE-2026-82649/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82649
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82649
- OSV: https://osv.dev/vulnerability/CVE-2026-82649

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82649/
Summaries are generated and may contain mistakes; the official description above is the record.