# CVE-2026-35672: phpMyFAQ authentication bypass in REST API v4.0

Source: https://junglewise.ai/threats/cve-2026-35672-phpmyfaq-authentication-bypass-in-rest-api-v4-0  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-28. Updated: 2026-05-28  
License: CC BY 4.0 with a link back

CVE-2026-35672 · Severity: high · CVSS 7.5 · Published 2026-05-28

phpMyFAQ is an open-source knowledge base system used by organizations to manage and share frequently asked questions. A security flaw in its programming interface (API) allows unauthorized individuals to bypass security checks and modify the knowledge base. An attacker could use this to create fake FAQ entries, delete categories, or inject malicious links and phishing content into the public-facing site, potentially damaging the organization's reputation or misleading its users.

Technologies: [phpmyfaq/phpmyfaq (Packagist)](https://junglewise.ai/threats/technologies/phpmyfaq-phpmyfaq), [thorsten/phpmyfaq (Packagist)](https://junglewise.ai/threats/technologies/thorsten-phpmyfaq). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2026-35672 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35672 being exploited in the wild.

**How severe is CVE-2026-35672?** High severity, with a CVSS score of 7.5, published 28 May 2026.

**Which products and versions are affected?** phpmyfaq/phpmyfaq (Packagist) ECOSYSTEM:introduced=0,fixed=4.1.3; thorsten/phpmyfaq (Packagist) ECOSYSTEM:introduced=0,fixed=4.1.3.

**Is there a fix for CVE-2026-35672?** Yes. phpmyfaq/phpmyfaq (Packagist): upgrade to 4.1.3 or later; thorsten/phpmyfaq (Packagist): upgrade to 4.1.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-35672 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-35672?** Check whether you run phpmyfaq/phpmyfaq (Packagist) or thorsten/phpmyfaq (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- phpmyfaq/phpmyfaq (Packagist): upgrade to 4.1.3 or later

  ```sh
  composer require phpmyfaq/phpmyfaq:^4.1.3
  ```

- thorsten/phpmyfaq (Packagist): upgrade to 4.1.3 or later

  ```sh
  composer require thorsten/phpmyfaq:^4.1.3
  ```


## Technical details

An authentication bypass exists in phpMyFAQ's REST API v4.0 due to insecure default initialization of the 'api.apiClientToken' configuration. During installation, this token is seeded as an empty string. The 'hasValidToken()' method in 'AbstractController.php' performs a strict inequality check between the configured token and the 'x-pmf-token' HTTP header provided by the client. Because both values default to an empty string, an attacker can bypass authentication by simply providing an empty 'x-pmf-token' header. This allows unauthorized POST and PUT requests to endpoints such as '/api/v4.0/faq/create', '/api/v4.0/category', and '/api/v4.0/question'. The issue is resolved in version 4.1.3.

## Affected products

- thorsten phpMyFAQ < 4.1.3

## Identifiers

- CVE-2026-35672
- GHSA-gp95-j463-vv28

## Timeline

- 2026-05-14: advisory: Vendor security advisory published on GitHub
- 2026-05-28: disclosed: CVE published to NVD and VulnCheck advisory released

## References

- [https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-gp95-j463-vv28](https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-gp95-j463-vv28)
- [https://www.vulncheck.com/advisories/phpmyfaq-authentication-bypass-via-empty-api-token](https://www.vulncheck.com/advisories/phpmyfaq-authentication-bypass-via-empty-api-token)

## Related threats

- [phpMyFAQ SQL injection in StopWords::add()](https://junglewise.ai/threats/cve-2026-56738-phpmyfaq-sql-injection-in-stopwords-add)
- [phpMyFAQ SQL LIKE wildcard injection in chat user search](https://junglewise.ai/threats/cve-2026-47132-phpmyfaq-sql-like-wildcard-injection-in-chat-user-search)
- [phpMyFAQ two-factor authentication password bypass](https://junglewise.ai/threats/cve-2026-56737-phpmyfaq-two-factor-authentication-password-bypass)
- [phpMyFAQ stored XSS in admin FAQ editor via HTML entity bypass](https://junglewise.ai/threats/cve-2026-56736-phpmyfaq-stored-xss-in-admin-faq-editor-via-html-entity-bypass)
- [phpMyFAQ information disclosure of inactive FAQ content in public API](https://junglewise.ai/threats/cve-2026-57994-phpmyfaq-information-disclosure-of-inactive-faq-content-in-public)