CVE-2024-49682: Simple Membership Open Redirect Vulnerability

CVE-2024-49682 Overview

CVE-2024-49682 is an open redirect vulnerability in the Simple Membership plugin for WordPress developed by wp.insider. The flaw affects all versions up to and including 4.5.3. Attackers can craft URLs that appear to point to a trusted WordPress site but silently redirect victims to attacker-controlled destinations. This vulnerability is tracked under [CWE-601] (URL Redirection to Untrusted Site) and is primarily leveraged for phishing campaigns targeting membership site users.

Critical Impact
Attackers can weaponize the plugin's redirect handling to send authenticated members to credential-harvesting pages that appear to originate from a legitimate WordPress domain.

Affected Products

Simple Membership plugin (simple-membership) for WordPress
All versions from initial release through 4.5.3
WordPress sites using the simple-membership-plugin by wp.insider

Discovery Timeline

2024-10-24 - CVE-2024-49682 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-49682

Vulnerability Analysis

The Simple Membership plugin exposes a redirect parameter that fails to validate the destination URL against an allowlist of trusted hosts. An unauthenticated attacker constructs a link pointing to the vulnerable WordPress endpoint and appends an attacker-controlled URL as the redirect target. When a victim clicks the link, the plugin issues an HTTP redirect that moves the browser to the external destination without warning.

The vulnerability requires user interaction, since the victim must follow the crafted link. The scope is changed because the redirect crosses the trust boundary from the WordPress site to an attacker-controlled origin. Impact is limited to confidentiality and integrity of session data captured through phishing, rather than direct compromise of the WordPress server.

Open redirects like this one are commonly chained with phishing kits that clone the legitimate login page. Because the initial URL displays the trusted WordPress domain, email gateways and users are more likely to trust the link.

Root Cause

The plugin accepts a redirect target from a request parameter and passes it to a redirect function without verifying that the destination belongs to the same origin or an approved list. Missing input validation on the redirect parameter is the direct cause, consistent with [CWE-601].

Attack Vector

Exploitation is network-based and requires no authentication or privileges. The attacker delivers a crafted URL through email, chat, or a compromised web page. The victim's click triggers the redirect from the trusted WordPress domain to an attacker-hosted site. See the Patchstack WordPress Vulnerability Report for technical details on the vulnerable parameter and endpoint.

No public proof-of-concept exploit is currently listed, and the vulnerability is not present in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2024-49682

Indicators of Compromise

Web server access logs showing requests to Simple Membership endpoints containing external URLs in redirect_to, redirect, or similar query parameters
HTTP 302 responses from the WordPress site pointing to domains outside the site's own origin
Referrer headers on external domains showing the WordPress site as the source of traffic to unfamiliar destinations
User reports of unexpected redirects after clicking links that appeared to point to the membership site

Detection Strategies

Inspect web application firewall (WAF) logs for requests where redirect parameters contain fully qualified URLs to third-party domains
Correlate outbound redirect events with recent phishing campaign intelligence targeting WordPress membership sites
Alert on any redirect response from Simple Membership endpoints whose Location header does not match the site's own domain

Monitoring Recommendations

Enable verbose access logging on all /wp-content/plugins/simple-membership/ request paths
Track version metadata of installed WordPress plugins and flag any instance of Simple Membership at or below 4.5.3
Feed WordPress and reverse proxy logs into a centralized analytics platform to baseline normal redirect behavior and surface anomalies

How to Mitigate CVE-2024-49682

Immediate Actions Required

Upgrade the Simple Membership plugin to the version released after 4.5.3 that addresses this open redirect flaw
Audit all WordPress sites in the environment for the presence of the simple-membership plugin and record installed versions
Educate members about phishing risks and instruct them to verify the final destination of any redirect before entering credentials

Patch Information

The vendor addressed CVE-2024-49682 in a release after Simple Membership 4.5.3. Refer to the Patchstack WordPress Vulnerability Report for the fixed version and vendor references. Apply the update through the WordPress plugin manager or by replacing the plugin files directly.

Workarounds

Deploy a WAF rule that blocks requests to Simple Membership endpoints when redirect parameters contain external URLs or protocol-relative paths
Restrict outbound redirects at the reverse proxy layer by rewriting or stripping Location headers that point outside the site's own domain
Temporarily disable the Simple Membership plugin on sites where patching is not immediately possible

bash

# Example WAF rule (ModSecurity) to block external redirects on Simple Membership endpoints
SecRule REQUEST_URI "@contains /simple-membership" \
    "chain,id:1004982,phase:2,deny,status:403,msg:'CVE-2024-49682 open redirect attempt'"
    SecRule ARGS:redirect_to|ARGS:redirect "@rx ^(https?:)?//(?!yoursite\.com)" \
        "t:none,t:lowercase"