Lemur: Authenticated low-privilege users can read plaintext destination credentials (SFTP password / private-key passphrase) via the destinations API

Exploitation

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

CVSS

7.7 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

EPSS

• CVE-2026-71307: 0.31% estimated exploitation activity in the next 30 days; percentile 24.41 (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 Lemur's destination read endpoints -- GET /api/1/destinations and GET /api/1/destinations/<id -- return the full set of stored plugin option values to any authenticated user, with no authorization check and no redaction of secret-bearing options. The sibling write endpoints (POST/PUT/DELETE) are gated with @adminpermission.require(httpexception=403), but the two read handlers are protected only by loginrequired (inherited from AuthenticatedResource). They do not even exclude read-only users. The built-in SFTP destination plugin (sftp-destination) stores its password and privateKeyPass options in cleartext in the destinations.options column (the plugin's own docstring states "Passwords are not encrypted and stored as a plain text."). Because DestinationOutputSchema serializes every option value verbatim, any authenticated principal -- including a read-only user -- can retrieve these credentials and use them to authenticate to the remote SFTP server to which Lemur deploys…

Published by the source

18 Aug 2026, 20:51 UTC

Last modified by the source

18 Aug 2026, 20:51 UTC

Source last checked

26 Oct 2026, 13:50 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-6c8m-q6g9-vrw3

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-71307

Advisory: Lemur: Authenticated low-privilege users can read plaintext destination credentials (SFTP password / private-key passphrase) via the destinations API
IDs: CVE-2026-71307, GHSA-6c8m-q6g9-vrw3
Record: https://patchnext.com/advisories/cve-2026-71307 (revision 1, source checked 26 Oct 2026, 13:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: lemur 1.9.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI lemur: affected < 1.9.3; fixed in 1.9.3

## Suggested inspection (read-only)
- `python -m pip show lemur`: prints the installed version. Run with the environment that serves production active.

## 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 lemur.
- 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-6c8m-q6g9-vrw3 (GitHub-reviewed advisory GHSA-6c8m-q6g9-vrw3 lists affected ranges: PyPI lemur >=0 <1.9.3)

Commands are suggestions: review each one before running it.