# CVE-2026-75594: Kirby: Access to image files and limited access to JSON files outside of the site root via path traversal in the media handling

> Attackers can traverse directories to read arbitrary JSON files and delete job files via crafted media requests on specific server configurations.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 31 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-9vx2-j98c-p72w

## What is CVE-2026-75594?

CVE-2026-75594 is a high-severity path traversal vulnerability in getkirby kirby, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Kirby is an open-source content management system. Prior to 4.9.5 and 5.5.2, depending on the release line, Kirby's media handler in src/Cms/Media.php allowed Kirby\Cms\Media::thumb() to append a path-bearing filename to a validated parent media directory. On nginx, PHP's built-in server, or Apache with AllowEncodedSlashes enabled, a remote attacker could submit encoded slash characters such as %2f in the filename and traverse outside the parent's media directory. Differences between responses for existing and nonexistent thumbnail configurations disclosed whether an arbitrary .json file existed, and a .json file containing a valid filename key could cause the referenced image to be returned and the job file to be deleted. The related file::version path in src/Filesystem/Asset.php also accepted ../ sequences outside the intended index root. This issue is fixed in versions 4.9.5 and 5.5.2.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-75594?

4 open source packages ship an affected version, including getkirby/cms.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `getkirby/cms` | Packagist | All versions | 4.9.5 |
| `getkirby/cms` | Packagist | All versions | 4.9.5 |
| `getkirby/cms` | Packagist | From 5.0.0 | 5.5.2 |
| `getkirby/cms` | Packagist | From 5.0.0 | 5.5.2 |

## How do I fix CVE-2026-75594?

Upgrade getkirby/cms to a fixed version for your release line: 4.9.5 or 5.5.2.

## Is CVE-2026-75594 being exploited?

There is no known exploitation of CVE-2026-75594 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75594 and fix it if it is affected.

What it is: CVE-2026-75594 is a high-severity path traversal vulnerability in getkirby kirby, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-75594 in the wild and no public exploit code.

Affected packages and fixed versions:
- getkirby/cms (Packagist): affected all versions; fixed in 4.9.5
- getkirby/cms (Packagist): affected all versions; fixed in 4.9.5
- getkirby/cms (Packagist): affected from 5.0.0; fixed in 5.5.2
- getkirby/cms (Packagist): affected from 5.0.0; fixed in 5.5.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-75594/ (Markdown: https://insights.sbomify.com/CVE-2026-75594/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75594
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75594
- OSV: https://osv.dev/vulnerability/CVE-2026-75594

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75594/
Summaries are generated and may contain mistakes; the official description above is the record.