Quantum Secular Labs / Blog / Advisories
CVE-2026-15413: The Link Factory WordPress plugin is a backdoor.
CVE-2026-15413 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. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
The Link Factory WordPress plugin is a backdoor. Distributed as a "homepage sentence publisher", it exposes an operator-controlled REST API under /wp-json/link-factory/v1/ - authenticated by a detached Ed25519 signature verified against a hardcoded operator public key (except for the health check).
Severity breakdown
CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/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: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-912: Hidden Functionality
The product contains functionality that is not documented, not part of the specification, and not accessible through an interface or command sequence that is obvious to the product's users or administrators.