CVE-2026-35672 is a high-severity security vulnerability in thorsten/phpmyfaq (composer), affecting versions <= 4.1.2. It is fixed in 4.1.3.
Summary A default empty API client token allows any unauthenticated user to create and modify FAQ entries, categories, and questions via the REST API. The vulnerability exists in all versions since API v4.0 was introduced because the installation process seeds api.apiClientToken with an empty string, and the hasValidToken() comparison logic cannot distinguish between "no token configured" and "attacker sent a matching empty token header." Details The root cause is in two files: Installation default (src/phpMyFAQ/Setup/Installation/DefaultDataSeeder.php, line 277-278): Authentication check (src/phpMyFAQ/Controller/AbstractController.php, line 198-204): The method uses strict inequality (!==). When api.apiClientToken is '' (default) and the attacker sends x-pmf-token: (empty header value), the comparison becomes '' !== '' which evaluates to false, no exception is thrown, and authentication is completely bypassed. The OpenAPI annotations confirm the developer intended these endpoints to require authentication: write endpoints are tagged 'Endpoints with Authentication' and document HTTP 401 responses, while read-only endpoints are tagged 'Public Endpoints'. The following API endpoints call $this->hasValidToken() as their only authentication check: | File | Endpoint | Method | | ------------------------------------------------------- | ---------------------- | ------ | | src/.../Controller/Api/FaqController.php:701-703 | /api/v4.0/faq/create | POST | | src/.../Controller/Api/FaqController.php:857-859 | /api/v4.0/faq/update | PUT | | src/.../Controller/Api/CategoryController.php:278-280 | /api/v4.0/category | POST | | src/.../Controller/Api/QuestionController.php:89-91 | /api/v4.0/question | POST | PoC Environment: phpMyFAQ 4.2.0-alpha, PHP 8.4.16, SQLite, installed with all defaults. Step 1, Verify that requests without auth header are correctly rejected: Response (HTTP 401, correctly blocked): Step 2, Send the same request with an empty x-pmf-token header: Response (HTTP 201, bypass confirmed): Step 3, Category creation via the same bypass: Response (HTTP 201): Step 4, Verify injected content is publicly visible: Response (HTTP 200, injected FAQ publicly exposed): PoC with Python (urllib, no external dependencies): Overlap Summary: | Test | x-pmf-token | HTTP Status | Result | | ------------------- | -------------- | ---------------- | -------------------------- | | No auth header | (not sent) | 401 Unauthorized | 🔒 Correctly blocked | | Empty token header | "" | 201 Created | 🔓 Bypass confirmed | | Category creation | "" | 201 Created | 🔓 Bypass confirmed | | Public verification | (not needed) | 200 OK | 📄 Injected content visible | Impact This is an authentication bypass (CWE-1188) affecting any phpMyFAQ installation where the administrator has not explicitly set a non-empty API client token, which is the default state after installation. Who is impacted? Any organization running phpMyFAQ with default configuration. The REST API is enabled by default, and the token defaults to empty. No action by the administrator is required for the vulnerability to exist, it is the out-of-the-box state. What can an attacker do? Create and modify FAQ entries, categories, and questions without any authentication. This enables content injection for phishing, SEO spam, reputation damage, and distribution of malicious links through the knowledge base. What is NOT affected? Read-only API endpoints are intentionally public. Session-authenticated admin endpoints are not affected. File upload and backup endpoints require separate session-based authentication.
CVE-2026-35672 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (4.1.3). Upgrading removes the vulnerable code path.
composer
thorsten/phpmyfaq (<= 4.1.2)phpmyfaq/phpmyfaq (<= 4.1.2)thorsten/phpmyfaq → 4.1.3 (composer)phpmyfaq/phpmyfaq → 4.1.3 (composer)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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Already deployed Kodem? See CVE-2026-35672 in your environment →Upgrade the following packages to resolve this vulnerability:
thorsten/phpmyfaq to 4.1.3 or laterphpmyfaq/phpmyfaq to 4.1.3 or laterKodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-35672 is a high-severity security vulnerability in thorsten/phpmyfaq (composer), affecting versions <= 4.1.2. It is fixed in 4.1.3.
CVE-2026-35672 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
thorsten/phpmyfaq (composer) (versions <= 4.1.2)phpmyfaq/phpmyfaq (composer) (versions <= 4.1.2)Yes. CVE-2026-35672 is fixed in 4.1.3. Upgrade to this version or later.
Whether CVE-2026-35672 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
thorsten/phpmyfaq to 4.1.3 or laterphpmyfaq/phpmyfaq to 4.1.3 or later