How severe is CVE-2016-3163?

CVE-2016-3163 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2016-3163?

CVE-2016-3163 affects the following packages: drupal/core (Packagist), drupal/core (Packagist), drupal/drupal (Packagist), drupal/drupal (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2016-3163?

Update drupal/core to 7.43 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-3163 is resolved across your whole dependency graph.

How do I detect CVE-2016-3163 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2016-3163 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2016-3163?

O3 pinpoints whether CVE-2016-3163 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2016-3163 actively exploited in the wild?

No public exploit code has been indexed for CVE-2016-3163 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What type of vulnerability is CVE-2016-3163?

CVE-2016-3163 is classified as CWE-254 (CWE-254). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2016-3163 published, and has it been updated?

CVE-2016-3163 was published on April 12, 2016 and was last updated on July 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

CVE-2016-3163

HIGH

CVE-2016-3163 is a high-severity (CVSS 7.5) CWE-254 vulnerability in drupal/core. O3 Security confirms whether CVE-2016-3163 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Drupal Brute force amplification attacks via XML-RPC

Also known asGHSA-h3r9-pjmr-f938

Published

Apr 12, 2016

Updated

Jul 8, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Blast Radius

4 pkgs affected

🐘drupal/core🐘drupal/core🐘drupal/drupal🐘drupal/drupal

Real-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

The XML-RPC system in Drupal 6.x before 6.38 and 7.x before 7.43 might make it easier for remote attackers to conduct brute-force attacks via a large number of calls made at once to the same method.

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`drupal/core`	≥ 7.0&&< 7.43	7.43
🐘Packagist	`drupal/core`	≥ 6.0&&< 6.38	6.38
🐘Packagist	`drupal/drupal`	≥ 7.0&&< 7.43	7.43
🐘Packagist	`drupal/drupal`	≥ 6.0&&< 6.38	6.38

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update drupal/core to 7.43 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-3163 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 pinpoints whether CVE-2016-3163 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2016-3163. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

The XML-RPC system in Drupal 6.x before 6.38 and 7.x before 7.43 might make it easier for remote attackers to conduct brute-force attacks via a large number of calls made at once to the same method.

O3 Security · Impact-Aware SCA

Is CVE-2016-3163 in your dependencies?

O3 detects CVE-2016-3163 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works