How severe is GHSA-wjw2-4j7j-6gc3?

GHSA-wjw2-4j7j-6gc3 has a CVSS score of 2/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-wjw2-4j7j-6gc3?

GHSA-wjw2-4j7j-6gc3 affects the following packages: wintercms/winter (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-wjw2-4j7j-6gc3?

Update wintercms/winter to 1.2.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wjw2-4j7j-6gc3 is resolved across your whole dependency graph.

How do I detect GHSA-wjw2-4j7j-6gc3 in my Packagist dependencies?

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

How do I mitigate GHSA-wjw2-4j7j-6gc3 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 GHSA-wjw2-4j7j-6gc3 actively exploited in the wild?

Yes. There are 2 known exploit references for GHSA-wjw2-4j7j-6gc3, including 1 documented proof-of-concept exploit on Exploit-DB and 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for GHSA-wjw2-4j7j-6gc3?

GHSA-wjw2-4j7j-6gc3 has an EPSS (Exploit Prediction Scoring System) score of 2.7%, placing it in the 85th 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 GHSA-wjw2-4j7j-6gc3?

GHSA-wjw2-4j7j-6gc3 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 GHSA-wjw2-4j7j-6gc3 published, and has it been updated?

GHSA-wjw2-4j7j-6gc3 was published on July 7, 2023 and was last updated on September 10, 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

LOW severity

GHSA-wjw2-4j7j-6gc3 — wintercms/winter

LOWFix: wintercms/storm@186d85d

GHSA-wjw2-4j7j-6gc3 is a low-severity (CVSS 2) Cross-site Scripting (XSS) vulnerability in wintercms/winter. 2 public exploit references exist, so weaponization risk is real. A fix is available for wintercms/winter — see the affected versions and patch details below.

Winter CMS stored XSS through privileged upload of SVG file

Also known asCVE-2023-37269

Published

Jul 7, 2023

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

2 known

Exploitation data as of Sep 26, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs85th percentile — riskier than 85% of all scored CVEsHighest risk

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

How urgent is this, really

GHSA-wjw2-4j7j-6gc3 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐘wintercms/winter

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

Users with the backend.manage_branding permission can upload SVGs as the application logo. Previously, SVG uploads were not sanitized, which could have allowed a stored XSS attack.

Although this was a security issue, it's important to note that its severity is low. To exploit the vulnerability, an attacker would already need to have developer or super user level permissions in Winter CMS. This means they would already have extensive access and control within the system. Additionally, to execute the XSS, the attacker would need to convince the victim to directly visit the URL of the maliciously uploaded SVG, and the application would have to be using local storage where uploaded files are served under the same domain as the application itself instead of a CDN. This is because all SVGs in Winter CMS are rendered through an img tag, which prevents any payloads from being executed directly.

These two factors significantly limit the potential harm of this vulnerability. That being said, all users are advised to update to the latest version (1.2.3) to ensure their systems remain secure.

Patches

This issue has been patched in v1.2.3 through the inclusion of full support for SVG uploads and automatic sanitization of uploaded SVG files.

Workarounds

Apply https://github.com/wintercms/storm/commit/186d85d8fea2cae43afc807d39f68553c24e56be & https://github.com/wintercms/winter/commit/fa50b4c7489b67ea80072f8ac9fe5294fce1df1c manually if unable to upgrade to v1.2.3.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`wintercms/winter`	all versions	1.2.3`composer require wintercms/winter:^1.2.3`

Affected Products

1 product · 1 configurations

Application

winterwintercms

< 1.2.3

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-51591webappsphp

WinterCMS < 1.2.3 - Persistent Cross-Site Scripting

by abhishek morla · Jul 15, 2023

Exploit-DB Source

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for wintercms/winter, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update wintercms/winter to 1.2.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wjw2-4j7j-6gc3 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 Users with the `backend.manage_branding` permission can upload SVGs as the application logo. Previously, SVG uploads were not sanitized, which could have allowed a stored XSS attack. Although this was a security issue, it's important to note that its severity is low. To exploit the vulnerability, an attacker would already need to have developer or super user level permissions in Winter CMS. This means they would already have extensive access and control within the system. Additionally, to execute the XSS, the attacker would need to convince the victim to directly visit the URL of