CVE-2021-4244 — yikesinc/yikes-inc-easy-m…
MEDIUMFix: EvanHerman/yikes-inc-easy-mailchimp-extender@3662c65CVE-2021-4244 is a medium-severity (CVSS 6.1) CWE-707 vulnerability in yikesinc/yikes-inc-easy-mailchimp-extender. A fix is available for yikesinc/yikes-inc-easy-mailchimp-extender — see the affected versions and patch details below.
yikes-inc-easy-mailchimp-extender Cross-site Scripting vulnerability
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-2021-4244.
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-2021-4244 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
yikesinc/yikes-inc-easy-mailchimp-extenderReal-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
A vulnerability classified as problematic has been found in yikes-inc-easy-mailchimp-extender Plugin up to 6.8.5. This affects an unknown part of the file admin/partials/ajax/add_field_to_form.php. The manipulation of the argument field_name/merge_tag/field_type/list_id leads to cross site scripting. It is possible to initiate the attack remotely. Upgrading to version 6.8.6 is able to address this issue. The name of the patch is 3662c6593aa1bb4286781214891d26de2e947695. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-215307.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | yikesinc/yikes-inc-easy-mailchimp-extender | all versions | 6.8.6composer require yikesinc/yikes-inc-easy-mailchimp-extender:^6.8.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for yikesinc/yikes-inc-easy-mailchimp-extender, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update yikesinc/yikes-inc-easy-mailchimp-extender to 6.8.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-4244 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-2021-4244 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-4244. 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-2021-4244 in your dependencies?
O3 Security finds CVE-2021-4244 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.