GHSA-jm9m-rqr3-wfmh is a high-severity (CVSS 8.1) CWE-863 vulnerability in getkirby/cms. A fix is available for getkirby/cms — see the affected versions and patch details below.
Kirby has insufficient permission checks in the language settings
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-jm9m-rqr3-wfmh.
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
GHSA-jm9m-rqr3-wfmh 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 377,166 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 with enabled languages option that might have potential attackers in the group of authenticated Panel users.
If you have disabled the languages and/or api option and don't call any methods in your code that cause a write access to languages (language creation, update or deletion), your site is not affected.
Introduction
Kirby allows to restrict the permissions of specific user roles. Users of that role can only perform permitted actions.
Permissions for creating and deleting languages have already existed and could be configured, but were not enforced by Kirby's frontend or backend code.
A permission for updating existing languages has not existed before the patched versions. So disabling the languages.* wildcard permission for a role could not have prohibited updates to existing language definitions.
Impact
The missing permission checks allowed attackers with Panel access to manipulate the language definitions.
The language definitions are at the core of multi-language content in Kirby. Unauthorized modifications with malicious intent can cause significant damage, for example:
- If the
languagesoption was enabled but no language exists, creating the first language will switch Kirby to multi-language mode. - Deleting an existing language will lead to content loss of all translated content in that language. Deleting the last language will switch Kirby to single-language mode.
- Updating a language allows to change the metadata including the language slug (used in page URLs) and language variables. It also allows to change the default language, which will cause Kirby to use the new default language's content as a fallback for non-existing translations.
Depending on the site code, the result of such actions can cause loss of site availability (e.g. error messages in the site frontend) or integrity (due to changed URLs or removed translations).
Patches
The problem has been patched in Kirby 3.6.6.6, Kirby 3.7.5.5, Kirby 3.8.4.4, Kirby 3.9.8.2, Kirby 3.10.1.1, and Kirby 4.3.1. Please update to one of these or a later version to fix the vulnerability.
In all of the mentioned releases, we have added checks for the languages.create and languages.delete permissions that ensure that users without those permissions cannot perform the respective actions. We have also added a new languages.update permission.
Credits
Thanks to Sebastian Eberlein of JUNO (@SebastianEberlein-JUNO) for reporting the identified issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getkirby/cms | all versions | 3.6.6.6composer require getkirby/cms:^3.6.6.6 |
| 🐘Packagist | getkirby/cms | ≥ 3.7.0&&< 3.7.5.5 | 3.7.5.5composer require getkirby/cms:^3.7.5.5 |
| 🐘Packagist | getkirby/cms | ≥ 3.8.0&&< 3.8.4.4 | 3.8.4.4composer require getkirby/cms:^3.8.4.4 |
| 🐘Packagist | getkirby/cms | ≥ 3.9.0&&< 3.9.8.2 | 3.9.8.2composer require getkirby/cms:^3.9.8.2 |
| 🐘Packagist | getkirby/cms | ≥ 3.10.0&&< 3.10.1.1 | 3.10.1.1composer require getkirby/cms:^3.10.1.1 |
| 🐘Packagist | getkirby/cms | ≥ 4.0.0&&< 4.3.1 | 4.3.1composer require getkirby/cms:^4.3.1 |
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 3.6.6.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jm9m-rqr3-wfmh 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 GHSA-jm9m-rqr3-wfmh can be triaged on real exposure rather than presence alone.
Tailored to GHSA-jm9m-rqr3-wfmh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-jm9m-rqr3-wfmh in your dependencies?
O3 Security finds GHSA-jm9m-rqr3-wfmh across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.