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

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-63188: 0.54% estimated exploitation activity in the next 30 days; percentile 45.49 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary @logto/tunnel serves custom sign-in experience files from the --experience-path directory. When the tunnel service is reachable, a requester can use ../ path segments in a static asset request to read files outside that directory that the CLI process can read. Details The tunnel command accepts --experience-path as the local folder path for custom sign-in experience assets. packages/tunnel/src/commands/tunnel/index.ts enables createStaticFileProxy(path) when that option is set and sends non-Logto, non---experience-uri requests to that static proxy. The server is started with server.listen(port). packages/tunnel/src/commands/tunnel/utils.ts builds the filesystem path as path.join(staticPath, fallBackToIndex ? index : request.url). For file asset paths, request.url is used directly. A request URL such as /../secret.txt resolves outside staticPath and is then opened with fs.open(requestPath, 'r'). There is no URL normalization and no containment check that the resolved path…

Published by the source

19 Aug 2026, 20:24 UTC

Last modified by the source

19 Aug 2026, 20:24 UTC

Source last checked

26 Oct 2026, 13:01 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-rxjr-6c9q-h67x

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# Patch Next advisory brief: CVE-2026-63188

Advisory: logto-tunnel serves files outside --experience-path via path traversal
IDs: CVE-2026-63188, GHSA-rxjr-6c9q-h67x
Record: https://patchnext.com/advisories/cve-2026-63188 (revision 1, source checked 26 Oct 2026, 13:01 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @logto/tunnel 0.3.9. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @logto/tunnel: affected <= 0.3.8; fixed in 0.3.9

## Suggested inspection (read-only)
- `npm ls @logto/tunnel --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @logto/tunnel.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-rxjr-6c9q-h67x (GitHub-reviewed advisory GHSA-rxjr-6c9q-h67x lists affected ranges: npm @logto/tunnel >=0 <=0.3.8)

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