CVE-2026-34974 phpMyFAQ: SVG Sanitizer Bypass via HTML Entity Encoding leads to Stored XSS and Privilege Escalation
Attackers with edit permissions can bypass SVG sanitization to inject JavaScript, leading to stored XSS and privilege escalation to admin.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-34974?
CVE-2026-34974 is a medium-severity cross-site scripting vulnerability in Phpmyfaq Phpmyfaq, published on 2 Apr 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
phpMyFAQ is an open source FAQ web application. Prior to version 4.1.1, the regex-based SVG sanitizer in phpMyFAQ (SvgSanitizer.php) can be bypassed using HTML entity encoding in javascript: URLs within SVG <a href> attributes. Any user with edit_faq permission can upload a malicious SVG that executes arbitrary JavaScript when viewed, enabling privilege escalation from editor to full admin takeover. This issue has been patched in version 4.1.1.
Weakness: CWE-79
Which versions are affected by CVE-2026-34974?
2 open source packages ship an affected version, including thorsten/phpmyfaq. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
thorsten/phpmyfaq Packagist | All versions | 4.1.1 |
thorsten/phpmyfaq Packagist | All versions | 4.1.1 |
Products include Phpmyfaq Phpmyfaq.
How do I fix CVE-2026-34974?
Upgrade thorsten/phpmyfaq to 4.1.1 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-34974 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34974 exists.
Other vulnerabilities in Phpmyfaq Phpmyfaq
- CVE-2023-0310 Cross-site Scripting (XSS) - Stored in thorsten/phpmyfaq
- CVE-2022-4407 Cross-site Scripting (XSS) - Reflected in thorsten/phpmyfaq
- CVE-2017-11187 Security feature bypass in n/a
- CVE-2026-76213 phpMyFAQ before 4.1.7 2FA Brute-Force via Session-Scoped Throttle
- CVE-2026-76214 phpMyFAQ before 4.1.7 WebAuthn Replay Attack via Challenge
Sources
Also known as GHSA-5crx-pfhq-4hgg.