How severe is GHSA-39cp-6679-8xv2?

No CVSS score has been assigned to GHSA-39cp-6679-8xv2 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-39cp-6679-8xv2?

GHSA-39cp-6679-8xv2 affects the following packages: getkirby/cms (Packagist), getkirby/cms (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-39cp-6679-8xv2?

Update getkirby/cms to 4.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-39cp-6679-8xv2 is resolved across your whole dependency graph.

How do I detect GHSA-39cp-6679-8xv2 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getkirby/cms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-39cp-6679-8xv2 if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-39cp-6679-8xv2?

O3 pinpoints whether GHSA-39cp-6679-8xv2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-39cp-6679-8xv2 actively exploited in the wild?

No public exploit code has been indexed for GHSA-39cp-6679-8xv2 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.

When was GHSA-39cp-6679-8xv2 published, and has it been updated?

GHSA-39cp-6679-8xv2 was published on May 4, 2026 and was last updated on May 13, 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

GHSA-39cp-6679-8xv2

GHSA-39cp-6679-8xv2 is a security vulnerability in getkirby/cms. O3 Security confirms whether GHSA-39cp-6679-8xv2 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Kirby CMS doesn't gate user avatar creation, replacement and deletion with user update permissions

Also known asCVE-2026-42174

Published

May 4, 2026

Updated

May 13, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Real-World Exposure

2 pkgs affected

🐘getkirby/cms🐘getkirby/cms

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

TL;DR

This vulnerability affects all Kirby sites where users of a particular role have no permission to update user information (user.update or users.update permission is disabled). This can be due to configuration in the blueprint(s) of the acting users, via options in the blueprint(s) of the target users or via a combination of both settings.

Kirby sites are not affected if they intend all users of the site to be able to upload, replace or delete user avatars. The vulnerability can only be exploited by authenticated users.

Introduction

Missing authorization allows authenticated users to perform actions they are not intended to have access to.

The effects of missing authorization can include unauthorized access to sensitive information as well as unauthorized changes to content or system information.

Impact

Kirby's user permissions control which user role is allowed to perform specific actions to content models in the CMS. These permissions are defined for each role in the user blueprint (site/blueprints/users/...). It is also possible to customize the permissions for each target model using the options feature (for user models again in the user blueprints). The permissions and options together control the authorization of user actions.

Kirby provides the user.update and users.update permissions (among others) that control the authorization to update user information for the user's own data or the data of other users respectively. User files are separately gated by the files.create, files.replace and files.delete permissions (among others).

In affected releases, Kirby only checked the files.create and files.delete permissions during changes to user avatars. Even though avatars are an integral part of the user profile, they were not covered by the user.update and users.update permissions. This allowed users with just file permissions to create, replace or delete user avatars.

Patches

The problem has been patched in Kirby 4.9.0 and Kirby 5.4.0. Please update to one of these or a later version to fix the vulnerability.

In all of the mentioned releases, we have added additional permission checks for user.update/users.update when a user avatar is created, replaced or deleted. These permission checks apply in addition to the file permission checks (files.create, files.replace and files.delete). When a user avatar is replaced with a file of the same type, Kirby now consistently checks the files.replace permission instead of a combination of files.create and files.delete.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`getkirby/cms`	all versions	4.9.0
🐘Packagist	`getkirby/cms`	≥ 5.0.0&&< 5.4.0	5.4.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getkirby/cms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update getkirby/cms to 4.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-39cp-6679-8xv2 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 pinpoints whether GHSA-39cp-6679-8xv2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-39cp-6679-8xv2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### TL;DR This vulnerability affects all Kirby sites where users of a particular role have no permission to update user information (`user.update` or `users.update` permission is disabled). This can be due to configuration in the blueprint(s) of the acting users, via `options` in the blueprint(s) of the target users or via a combination of both settings. Kirby sites are *not* affected if they intend all users of the site to be able to upload, replace or delete user avatars. The vulnerability can only be exploited by authenticated users. ---- ### Introduction Missing authorization allows a

O3 Security · Impact-Aware SCA

Is GHSA-39cp-6679-8xv2 in your dependencies?

O3 detects GHSA-39cp-6679-8xv2 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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