How severe is CVE-2021-37710?

CVE-2021-37710 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-2021-37710?

CVE-2021-37710 affects the following packages: shopware/core (Packagist), shopware/platform (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2021-37710?

Update shopware/core to 6.4.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-37710 is resolved across your whole dependency graph.

How do I detect CVE-2021-37710 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for shopware/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-37710 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2021-37710 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-37710 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 is the EPSS score for CVE-2021-37710?

CVE-2021-37710 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 53th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-37710?

CVE-2021-37710 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-37710 published, and has it been updated?

CVE-2021-37710 was published on August 16, 2021 and was last updated on July 9, 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

Not in CISA KEV

MEDIUM severity

CVE-2021-37710 — core

MEDIUMFix: shopware/platform@abe9f69

CVE-2021-37710 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in shopware/core. A fix is available for shopware/core — see the affected versions and patch details below.

Cross-Site Scripting via SVG media files

Also known asGHSA-fc38-mxwr-pfhx

Published

Aug 16, 2021

Updated

Jul 9, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs53th percentile — riskier than 53% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2021-37710 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

🐘shopware/core🐘shopware/platform

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

Impact

Cross-Site Scripting via SVG media files

Patches

We recommend updating to the current version 6.4.3.1. You can get the update to 6.4.3.1 regularly via the Auto-Updater or directly via the download overview.

https://www.shopware.com/en/download/#shopware-6

Workarounds

For older versions of 6.1, 6.2, and 6.3, corresponding security measures are also available via a plugin. For the full range of functions, we recommend updating to the latest Shopware version.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`shopware/core`	all versions	6.4.3.1`composer require shopware/core:^6.4.3.1`
🐘Packagist	`shopware/platform`	all versions	6.4.3.1`composer require shopware/platform:^6.4.3.1`

Affected Products

1 product · 1 configurations

Application

shopwareshopware

< 6.4.3.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for shopware/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update shopware/core to 6.4.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-37710 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

### Impact Cross-Site Scripting via SVG media files ### Patches We recommend updating to the current version 6.4.3.1. You can get the update to 6.4.3.1 regularly via the Auto-Updater or directly via the download overview. https://www.shopware.com/en/download/#shopware-6 ### Workarounds For older versions of 6.1, 6.2, and 6.3, corresponding security measures are also available via a plugin. For the full range of functions, we recommend updating to the latest Shopware version.