logto-tunnel serves files outside --experience-path via path traversal (CVE-2026-63188) | HOL Guard CVE

High severityCVE-2026-63188GHSA-RXJR-6C9Q-H67X

logto-tunnel serves files outside --experience-path via path traversal

Answer in brief

CVE-2026-63188 records a High severity vulnerability in logto-tunnel serves files outside --experience-path via path traversal. The current sources do not mark it as known exploited. The current feed maps logto-io/logto (generic), @logto/tunnel (npm), @logto/tunnel (npm). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 19, 2026Updated Aug 19, 2026Source checked Aug 19, 2026First seen by HOL Aug 19, 2026Material review Aug 19, 2026

Upstream Advisory

Key facts

Risk: High
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps logto-io/logto (generic), @logto/tunnel (npm), @logto/tunnel (npm). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
logto-io/logtogeneric	< 0.3.9	Not reported
@logto/tunnelnpm	>=0 <0.3.9	0.3.9
@logto/tunnelnpm	<=0.3.8	0.3.9

Recommended response

Check inventory. Check lockfiles and deployed manifests for logto-io/logto, @logto/tunnel, @logto/tunnel.
Review the reported fix. Update @logto/tunnel to 0.3.9; @logto/tunnel to 0.3.9 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 19, 2026

Sources and claim methodology

Upstream source description

Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 0.3.9, the Logto Tunnel npm package enabled createStaticFileProxy from packages/tunnel/src/commands/tunnel/index.ts and passed request.url from static asset requests through packages/tunnel/src/commands/tunnel/utils.ts using path.join(staticPath, request.url) and then fs.open(requestPath, "r") without URL normalization or a containment check. When --experience-path was enabled and the tunnel port was reachable, an unauthenticated requester could send a path containing ../ to createStaticFileProxy and read files outside the configured static directory that were readable by the logto-tunnel process. The service used server.listen(port), which could expose the tunnel to other hosts depending on the platform and deployment. This issue is fixed in version 0.3.9.

Quoted source text, attributed separately from HOL analysis.