CVE-2025-66310 — getgrav/grav
Fix: getgrav/grav-plugin-admin@99f6532CVE-2025-66310 is a Cross-site Scripting (XSS) vulnerability in getgrav/grav. A fix is available for getgrav/grav — see the affected versions and patch details below.
Grav vulnerable to Cross-Site Scripting (XSS) Stored endpoint `/admin/pages/[page]` parameter `data[header][template]` in Advanced Tab
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-2025-66310.
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.
Real-World Exposure
getgrav/gravReal-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
A Stored Cross-Site Scripting (XSS) vulnerability was identified in the /admin/pages/[page] endpoint of the Grav application. This vulnerability allows attackers to inject malicious scripts into the data[header][template] parameter. The script is saved within the page's frontmatter and executed automatically whenever the affected content is rendered in the administrative interface or frontend view.
Details
Vulnerable Endpoint: POST /admin/pages/[page]
Parameter: data[header][template]
The application fails to properly sanitize user input in the data[header][template] field, which is stored in the YAML frontmatter of the page. An attacker can inject JavaScript code using this field, and the payload is rendered and executed when the page is accessed, especially within the Admin Panel interface.
PoC
Payload:
<script>alert('PoC-XXS73')</script>
Steps to Reproduce:
-
Log in to the Grav Admin Panel and navigate to Pages.
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Create a new page or edit an existing one.
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In the Advanced > Template field (which maps to
data[header][template]), insert the payload: -
Save the page.
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Return to the Pages section and click on the three-dot menu of the affected page:
-
The stored XSS payload is triggered, and the script is executed in the browser:
Impact
Stored XSS vulnerabilities can have serious consequences, including:
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Session hijacking: Capturing admin session cookies or tokens
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Malware delivery: Executing scripts that load malicious resources
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Credential theft: Creating fake login prompts to steal usernames/passwords
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Data exposure: Reading sensitive metadata or page contents
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Privilege escalation: Performing actions as an authenticated user
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Website defacement: Altering visual or functional elements of the site
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Reputation damage: Undermining user trust in the application
by CVE-Hunters
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getgrav/grav | all versions | 1.8.0-beta.27composer require getgrav/grav:^1.8.0-beta.27 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update getgrav/grav to 1.8.0-beta.27 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-66310 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-2025-66310 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-66310. 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-2025-66310 in your dependencies?
O3 Security finds CVE-2025-66310 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.