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Vulnerability Database

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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

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Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

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362,176

Total vulnerabilities in the database

obsidian-local-rest-api: Authenticated path traversal via URL-encoded %2F in /vault/{path} — arbitrary host file read/write/delete — obsidian-local-rest-api

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Summary

The Local REST API's /vault/{path} endpoints (GET/PUT/PATCH/POST/DELETE) percent-decode the request path inside the handler — after Express has already routed and normalized it, then hand it to the Obsidian vault adapter with no confinement check. A literal ../ is resolved/rejected at the routing layer (→ 404), but %2F is not a separator there, so ..%2F..%2F survives routing and is only turned into a real / by the handler's decodeURIComponent, reconstituting a ../ traversal that walks out of the vault. An authenticated client can read, write, or delete arbitrary files on the host with the Obsidian process's privileges.

Details

Framework: Express (import express from "express"; routes registered via this.api.route("/vault/*")…).

The vulnerable line — in src/requestHandler.ts, every vault handler (vaultGet, vaultPut, vaultPatch, vaultPost, vaultDelete) derives the path like this:

const rawPath = decodeURIComponent(
  req.path.slice(req.path.indexOf(&quot;/&quot;, 1) + 1),
);

The path is decodeURIComponent'd after Express routing. A literal ../ is collapsed/rejected at the routing layer, but %2F isn't a separator there — so ..%2F..%2F reaches the handler intact and this decodeURIComponent turns it into a real ../../. The string routing saw (…%2F…) is not the string the handler uses (…/…), and %2e%2e behaves the same way.

No confinement on the decoded path. The handlers pass rawPath straight to the vault adapter — e.g. this.app.vault.adapter.readBinary(filePath) / this.app.vault.getAbstractFileByPath(filePath) — with no path.resolve + vault-root prefix check, so the reconstituted ../../ escapes.

The fix already exists in your code — for MOVE only. vaultMove confines correctly:

const syntheticRoot = &quot;/vault&quot;;
const resolved = posix.resolve(syntheticRoot, normalized);
if (resolved !== syntheticRoot &amp;&amp; !resolved.startsWith(syntheticRoot + &quot;/&quot;)) {
  this.returnCannedResponse(res, { errorCode: ErrorCode.PathTraversalNotAllowed });
  return;
}

GET/PUT/PATCH/POST/DELETE lack this guard. Apply the same posix.resolve(syntheticRoot, …) + startsWith check to the decoded path in every vault handler, and reject any segment that decodes to ...

PoC

Prereq: a running Obsidian with the Local REST API plugin enabled and its configured API key ($API_KEY). Targets below are Unix; adjust per OS (e.g. ..%2F..%2FWindows%2Fwin.ini on Windows).

# READ outside the vault (returns 200 + the target file&#039;s real bytes):
curl --path-as-is -k -H &quot;Authorization: Bearer $API_KEY&quot; \
  &quot;https://127.0.0.1:27124/vault/..%2F..%2F..%2F..%2Fetc%2Fpasswd&quot;

# WRITE outside the vault (creates a file on disk outside the vault root):
curl --path-as-is -k -X PUT -H &quot;Authorization: Bearer $API_KEY&quot; --data &quot;pwned&quot; \
  &quot;https://127.0.0.1:27124/vault/..%2F..%2F..%2Ftmp%2Fcanary.txt&quot;

--path-as-is stops curl from collapsing .. client-side. A plain ../ (unencoded) request returns 404 — only the %2F/%2e%2e encoded form bypasses, confirming the decode-after-routing gap.

Impact

Authenticated arbitrary file read / write / delete outside the Obsidian vault, with the OS privileges of the Obsidian process — typically the user's home directory (SSH keys, browser profiles, dotfiles, credentials). Amplified in MCP/LLM-agent deployments: this API is widely used as an MCP server, so a prompt-injection in vault content (or a malicious MCP client) can make an agent emit a %2F path — turning "the agent can edit my notes" into "the agent can read/write any file on the host," with no user intent to grant filesystem access beyond the vault.

This vulnerability was reported by Caleb Brisbin through responsible disclosure.

Published: Jul 15, 2026
Updated: Jul 16, 2026
GHSA: GHSA-62gx-5q78-wrvx
Severity: High
Exploit:
CISA KEV:

CVSS v3:

Severity: High
Score: 8.8
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWEs:

CWE-22

OWASP TOP 10:

A5 - Broken Access Control

Affected Software
References

Software	From	Fixed in
obsidian-local-rest-api	-	4.1.3

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Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.