Quantum Secular Labs / Blog / Advisories
CVE-2026-71495: Wanderer: Authentication bypass
CVE-2026-71495 is rated critical with a CVSS v3.1 base score of 10.0. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.
Vulnerability description
Wanderer is a self-hosted trail database for saving and sharing adventures. Prior to 0.20.0, when PUBLIC_PRIVATE_INSTANCE is not set to true, the unauthenticated POST /api/v1/trail/download handler passes the attacker-controlled JSON url field directly to event.fetch() and returns the fetched response. This allows requests to internal services such as db:8090 and search:7700, cloud metadata addresses, and other network destinations, exposing returned data and permitting internal network reconnaissance or denial of service. This issue is fixed in version 0.20.0.
Severity breakdown
CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: None. No loss of integrity.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-918: Server-Side Request Forgery
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.