How severe is CVE-2016-5013?

CVE-2016-5013 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2016-5013?

CVE-2016-5013 affects the following packages: moodle/moodle (Packagist), moodle/moodle (Packagist), moodle/moodle (Packagist), moodle/moodle (Packagist), moodle/moodle (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2016-5013?

Update moodle/moodle to 3.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-5013 is resolved across your whole dependency graph.

How do I detect CVE-2016-5013 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle. 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-2016-5013 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-2016-5013?

O3 pinpoints whether CVE-2016-5013 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-2016-5013 actively exploited in the wild?

No public exploit code has been indexed for CVE-2016-5013 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-2016-5013?

CVE-2016-5013 is classified as CWE-74 (CWE-74). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2016-5013 published, and has it been updated?

CVE-2016-5013 was published on January 20, 2017 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-2016-5013

MEDIUM

CVE-2016-5013 is a medium-severity (CVSS 5.4) CWE-74 vulnerability in moodle/moodle. O3 Security confirms whether CVE-2016-5013 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Moodle Does Not Escape Characters In Email Headers

Also known asGHSA-2hh3-jmv8-5fmx

Published

Jan 20, 2017

Updated

Jul 8, 2026

Affected

5 pkgs

Patched

4 / 5

Exploits

None indexed

Blast Radius

5 pkgs affected

🐘moodle/moodle🐘moodle/moodle🐘moodle/moodle🐘moodle/moodle🐘moodle/moodle

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

In Moodle 2.x and 3.x, text injection can occur in email headers, potentially leading to outbound spam.

Affected Packages

5 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`moodle/moodle`	≥ 3.1&&< 3.1.1	3.1.1
🐘Packagist	`moodle/moodle`	≥ 3.0&&< 3.0.5	3.0.5
🐘Packagist	`moodle/moodle`	≥ 2.9&&< 2.9.7	2.9.7
🐘Packagist	`moodle/moodle`	≥ 2.8	No fix
🐘Packagist	`moodle/moodle`	≥ 2.7&&< 2.7.15	2.7.15

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle. 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 moodle/moodle to 3.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-5013 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-2016-5013 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-2016-5013. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

In Moodle 2.x and 3.x, text injection can occur in email headers, potentially leading to outbound spam.

O3 Security · Impact-Aware SCA

Is CVE-2016-5013 in your dependencies?

O3 detects CVE-2016-5013 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