CVE-2023-1938

WP Fastest Cache <= 1.1.4 - Authenticated(Administrator+) Blind Server Side Request Forgery via check_url

2023-05-02 00:00
Erwan LR

Strategic Overview

Status
Patched in 1.1.5
Affected Version
<= 1.1.4
CVSS
6.5Medium
Weakness type
CWE-918 · Server-Side Request Forgery (SSRF)
CVE
CVE-2023-1938
View all WP Fastest Cache – WordPress Cache Plugin vulnerabilities

At a glance

CVE-2023-1938 is a medium-severity Server-Side Request Forgery (SSRF) vulnerability in the WP Fastest Cache WordPress plugin, affecting versions <= 1.1.4. It carries a CVSS score of 6.5 (reachable over the network; low attack complexity; high integrity, availability impact). Exploitation requires an authenticated account at Administrator level or above. The issue is fixed in version 1.1.5; sites on affected versions should update now. Disclosed May 2023, reported by Erwan LR.

Vulnerability Overview

The WP Fastest Cache plugin for WordPress is vulnerable to Server-Side Request Forgery in versions up to, and including, 1.1.4 via the 'check_url' function. This can allow Authenticated attackers with Administrator-level permissions to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services. Note that the function is also vulnerable to Cross-Site Request Forgery but this is only an issue due to the Server-Side Request Forgery capability.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user. A successful exploit has high impact on integrity, availability.

CWE-918: Server-Side Request Forgery (SSRF)

WP Fastest Cache <= 1.1.4 carries this weakness at check_url, and reaching it takes an account at Administrator level or above. Server-side request forgery means the application fetches a URL supplied by the caller, turning the server into a proxy for requests the attacker could not make directly.

The request originates from inside the hosting network, which is how these flaws reach cloud metadata endpoints, internal admin panels and services that trust local traffic. For WP Fastest Cache the fix is 1.1.5: builds <= 1.1.4 are affected, anything from 1.1.5 onward is not.

Remediation

Update to version 1.1.5, or a newer patched version

How does WordSec protect against this?

An attacker needs Administrator access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WP Fastest Cache 1.1.5 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

Related records

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