# CVE-2026-104078: Obsidian Desktop < 1.14.0 RCE via MathJax Safe Filter Bypass

> Attackers can execute arbitrary OS commands by crafting malicious MathJax formulas that bypass URL filters in Obsidian Desktop.

- **Severity:** High 8.4 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 8 Oct 2026
- **Updated:** 27 Oct 2026
- **Also known as:** GHSA-4pcg-gm3h-3m4r

## What is CVE-2026-104078?

CVE-2026-104078 is a high-severity code injection vulnerability in Obsidian Desktop, published on 8 Oct 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

Obsidian Desktop before 1.14.0 contains a filter bypass vulnerability in the bundled MathJax 3.2.2 Safe component that allows attackers to execute arbitrary code by embedding a crafted \href value with a TAB byte in the URL scheme, causing filterURL to produce an empty protocol that bypasses the configured safeProtocols restrictions. Attackers can craft a note containing a malicious MathJax formula that renders as a javascript: URL anchor, which when clicked by the victim in Live Preview executes in the Node-integration-enabled vault renderer via require('child_process'), achieving arbitrary operating system command execution as the desktop user.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-1188 (Initialization of a Resource with an Insecure Default)

## Which versions are affected by CVE-2026-104078?


## How do I fix CVE-2026-104078?

No fix has been published for CVE-2026-104078 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-104078 being exploited?

There is no known exploitation of CVE-2026-104078 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104078 and fix it if it is affected.

What it is: CVE-2026-104078 is a high-severity code injection vulnerability in Obsidian Desktop, published on 8 Oct 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: There is no known exploitation of CVE-2026-104078 in the wild and no public exploit code.

Affected product: Obsidian Desktop. 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-2026-104078/ (Markdown: https://insights.sbomify.com/CVE-2026-104078/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104078
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104078
- OSV: https://osv.dev/vulnerability/CVE-2026-104078

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104078/
Summaries are generated and may contain mistakes; the official description above is the record.