CVE-2024-26483 — getkirby/cms
HIGHCVE-2024-26483 is a high-severity (CVSS 8.8) Code Injection vulnerability in getkirby/cms. A fix is available for getkirby/cms — see the affected versions and patch details below.
Kirby vulnerable to unrestricted file upload of user avatar images
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.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-26483.
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-2024-26483 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
getkirby/cms🐘getkirby/cms🐘getkirby/cms🐘getkirby/cms🐘getkirby/cms🐘getkirby/cmsReal-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
TL;DR
This vulnerability affects all Kirby sites that might have potential attackers in the group of authenticated Panel users.
The attack requires user interaction by another user or visitor and cannot be automated.
Introduction
Unrestricted upload of files with a dangerous type is a type of vulnerability that allows to circumvent expectations and protections in the server setup or backend code. Uploaded files are not checked for their compliance with the intended purpose of the upload target, which can introduce secondary attack vectors.
While the vulnerability described here does not allow critical attacks like remote code execution (RCE), it can still be abused to upload unexpected file types that could for example make it possible to perform cross-site scripting (XSS) attacks.
Impact
Users with Panel access can upload a user avatar in their own account view. This avatar is intended to be an image, however the file type or file extension was not validated on the backend. This effectively allowed to upload many types of files that would then be stored with the filename profile and the provided file extension.
While the upload is protected against dangerous file types such as HTML files or executable PHP files, this could be abused to upload unexpected files such as PDFs that would then be available via a direct link. These links could be shared to other users.
Patches
The problem has been patched in Kirby 3.6.6.5, Kirby 3.7.5.4, Kirby 3.8.4.3, Kirby 3.9.8.1, Kirby 3.10.0.1, and Kirby 4.1.1. Please update to one of these or a later version to fix the vulnerability.
In all of the mentioned releases, we have added validations that prevent any files that don't have an image file extension or MIME type from being uploaded as a user avatar.
Credits
Thanks to Natwara Archeepsamooth (@PlyNatwara) for responsibly reporting the identified issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getkirby/cms | all versions | 3.6.6.5composer require getkirby/cms:^3.6.6.5 |
| 🐘Packagist | getkirby/cms | ≥ 3.7.0&&< 3.7.5.4 | 3.7.5.4composer require getkirby/cms:^3.7.5.4 |
| 🐘Packagist | getkirby/cms | ≥ 3.8.0&&< 3.8.4.3 | 3.8.4.3composer require getkirby/cms:^3.8.4.3 |
| 🐘Packagist | getkirby/cms | ≥ 3.9.0&&< 3.9.8.1 | 3.9.8.1composer require getkirby/cms:^3.9.8.1 |
| 🐘Packagist | getkirby/cms | ≥ 3.10.0&&< 3.10.0.1 | 3.10.0.1composer require getkirby/cms:^3.10.0.1 |
| 🐘Packagist | getkirby/cms | ≥ 4.0.0&&< 4.1.1 | 4.1.1composer require getkirby/cms:^4.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getkirby/cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update getkirby/cms to 3.6.6.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-26483 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-2024-26483 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-26483. 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-2024-26483 in your dependencies?
O3 Security finds CVE-2024-26483 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.