CVE-2025-10583 is an authenticated Server-Side Request Forgery (SSRF) vulnerability in the WordPress plugin WP Fastest Cache, affecting versions up to and including 1.7.4 according to the NVD record. What makes this issue especially operationally relevant is the plugin’s adoption: the WordPress.org listing shows 1+ million active installations, so any low-privilege-to-network-recon bug has immediate “real internet” consequences across a large attack surface. The core impact is not a direct data exfiltration primitive by itself, but rather a reliable way for a low-privileged authenticated user to coerce the server into making outbound connections, which can be weaponized for internal network discovery, firewall bypass, and chaining into higher-impact compromises.
| CVE | CVE-2025-10583 |
| Plugin Version | WP Fastest Cache Premium <= 1.7.4 |
| All Time | 62 858 825 |
| Active installations | 1 000 000+ |
| Publicly Published | December 11, 2025 |
| Last Updated | December 11, 2025 |
| Researcher | Dmitrii Ignatyev |
| PoC | Yes |
| Exploit | No |
| Reference | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-10583 https://www.wordfence.com/threat-intel/vulnerabilities/wordpress-plugins/wp-fastest-cache-premium/wp-fastest-cache-premium-174-missing-authorization-to-authenticated-subscriber-blind-server-side-request-forgery https://t.me/cleantalk_researches/363 |
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| Logo of the plugin |  |
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Timeline
| August 28, 2025 | Plugin testing and vulnerability detection in the WP Fastest Cache have been completed |
| August 28, 2025 | I contacted the author of the plugin and provided a vulnerability PoC with a description and recommendations for fixing |
| December 11, 2025 | Registered CVE-2025-10583 |
Discovery of the Vulnerability
The Description attributes the issue to the get_server_time_ajax_request AJAX action, which can be abused by authenticated attackers with Subscriber-level access and above to make requests to arbitrary locations originating from the server. In your technical analysis, the vulnerable implementation pattern is consistent with “missing authorization + missing nonce”: the premium module registers the AJAX action without enforcing an appropriate current_user_can()gate and without requiring a nonce, then reads attacker-controlled URLs from servers[i][url] and initiates a network connection using fsockopen() with a short timeout. That combination matters because it turns what is presumably a “latency/time check” feature into a blind connection oracle: the attacker may not see full response content, but they can still learn whether a host:port is reachable based on timing and success/failure behavior.
Understanding of SSRF attack’s
Even though SSRF is not “sensitive data exposure” in the classic sense (like leaking wp-config.php), in WordPress environments it frequently becomes the bridge to sensitive information because the WordPress server often has network reachability that external attackers do not. Common examples include metadata services (cloud instance metadata endpoints), internal databases, internal admin panels, monitoring dashboards, Redis/Memcached, search backends, or “localhost-only” management interfaces that rely on network position for security rather than strong authentication. With SSRF, the attacker stops being “outside the perimeter” and starts leveraging the server as a proxy into otherwise unreachable network segments; this is why the NVD notes it can be used to “query and modify information from internal services,” even when the initial primitive looks like a simple outbound request mechanism. In practice, the most immediate harm is often reconnaissance (mapping internal services), but the downstream risk is credential theft, configuration disclosure, or lateral movement if any internal service is misconfigured or exposes sensitive operations to trusted subnets.
Exploiting the SSRF Vulnerability
To exploit CVE-2025-10583, an attacker with Subscriber+ cookies:
POC:
http://127.0.0.1/wordpress/wp-admin/admin-ajax.php?action=get_server_time_ajax_request&servers[0][url]=http://127.0.0.1:444____
The practical risk profile of CVE-2025-10583 is internal network reconnaissance and pivot enablement from a low-privilege account, not a single-click RCE. Once an attacker has a Subscriber account (which is common on membership sites, stores, LMS platforms, and community portals), they can use the WordPress server as a vantage point to probe internal RFC1918 address space, localhost-bound services, or cloud metadata endpoints that are frequently blocked from the public internet but reachable from the instance itself. This can directly undermine segmentation assumptions (“the admin panel is safe because it’s only on the internal network”), and it can expose hidden management services that were never intended to face untrusted users. Even when the SSRF is “blind,” it can still materially increase attack success by identifying where high-value services live, which ports are open, and which targets respond differently (fast connect vs timeout), enabling attackers to focus subsequent exploitation attempts where it’s most likely to work.
Recommendations for Improved Security
The remediation is conceptually simple: treat this endpoint as a privileged diagnostic action and enforce authorization, request authenticity, and strict destination validation. At minimum, the handler should require a strong capability gate (e.g., manage_options or a plugin-specific admin capability) and must require a nonce to prevent CSRF, because state-changing or network-active AJAX actions should not be callable by arbitrary authenticated users. The NVD’s weakness classification aligns with Missing Authorization, reinforcing that the primary fix is a correct capability check rather than superficial sanitization. On top of that, harden the network behavior: apply an allow-list of permitted targets (or disallow private/loopback/link-local ranges entirely), restrict ports, enforce a safe URL parser, and ensure the endpoint does not act as a timing oracle (for example, by returning a consistent response without leaking connect/timeout differences). Operationally, site owners should patch/upgrade beyond the vulnerable range (NVD: up to 1.7.4), review whether premium diagnostic features are exposed to non-admin roles, and consider egress controls at the infrastructure layer so that even if an SSRF primitive exists, it cannot reach sensitive internal destinations.
By taking proactive measures to address SSRF vulnerabilities like CVE-2025-13922 WordPress website owners can enhance their security posture and safeguard against potential exploitation. Stay vigilant, stay secure.
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