CVE-2026-24421 — phpmyfaq/phpmyfaq
MEDIUMCVE-2026-24421 is a medium-severity (CVSS 6.5) CWE-862 vulnerability in phpmyfaq/phpmyfaq. 1 public exploit reference exists, so weaponization risk is real. A fix is available for phpmyfaq/phpmyfaq — see the affected versions and patch details below.
phpMyFAQ: /api/setup/backup accessible to any authenticated user (authz missing)
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-24421.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-24421 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
phpmyfaq/phpmyfaq🐘thorsten/phpmyfaqReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Authenticated non‑admin users can call /api/setup/backup and trigger a configuration backup. The endpoint only checks authentication, not authorization, and returns a link to the generated ZIP.
Details
SetupController.php uses userIsAuthenticated() but does not verify that the requester has configuration/admin permissions. This allows any logged‑in user to create a sensitive backup and retrieve its path.
PoC
Precondition: API enabled, any authenticated non‑admin user.
- Log in as a non‑admin user.
- Call backup endpoint.
curl -c /tmp/pmf_api_cookies.txt \
-H 'Content-Type: application/json' \
-d '{"username":"tester","password":"Test1234!"}' \
http://192.168.40.16/phpmyfaq/api/v3.0/login
curl -i -b /tmp/pmf_api_cookies.txt \
-X POST --data '4.0.16' \
http://192.168.40.16/phpmyfaq/api/setup/backup
Impact
Low‑privileged users can generate sensitive backups. If the ZIP is web‑accessible (server misconfiguration), this can lead to secret exposure.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | phpmyfaq/phpmyfaq | all versions | 4.0.17composer require phpmyfaq/phpmyfaq:^4.0.17 |
| 🐘Packagist | thorsten/phpmyfaq | all versions | 4.0.17composer require thorsten/phpmyfaq:^4.0.17 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
phpMyFAQ 4.0.16 - Improper Authorization
by contact · Apr 29, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for phpmyfaq/phpmyfaq, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update phpmyfaq/phpmyfaq to 4.0.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24421 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-24421 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-24421. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-24421 in your dependencies?
O3 Security finds CVE-2026-24421 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.