# CVE-2026-72783: Craft CMS 5.0.0-RC1 before 5.10.6 Path Traversal via ensurePathIsContained

> Craft CMS contains a theoretical path traversal flaw in file system validation that could allow reading files outside intended directories, though no direct exploitation is known.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:L/AC:L/AT:N/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Aug 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-7hxc-f267-h5q7

## What is CVE-2026-72783?

CVE-2026-72783 is a medium-severity path traversal vulnerability in craftcms cms, published on 11 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Craft CMS versions >= 5.0.0-RC1 before 5.10.6 and >= 4.0.0-RC1 before 4.18.2 contain a theoretical path traversal weakness in the ensurePathIsContained function of the Local file system class. The order of operations validates the path before normalization, so normalization could invalidate prior validation assumptions (a desanitization-style issue) and potentially resolve to files outside the intended volume directory. The vendor notes the issue is not directly exploitable and no exploitable scenario has been discovered; the fix is recommended for hardening.

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

## Which versions are affected by CVE-2026-72783?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `craftcms/cms` | Packagist | From 4.0.0-RC1 | 4.18.2 |
| `craftcms/cms` | Packagist | From 4.0.0-RC1 | 4.18.2 |
| `craftcms/cms` | Packagist | From 5.0.0-RC1 | 5.10.6 |
| `craftcms/cms` | Packagist | From 5.0.0-RC1 | 5.10.6 |

## How do I fix CVE-2026-72783?

Upgrade craftcms/cms to a fixed version for your release line: 4.18.2 or 5.10.6.

## Is CVE-2026-72783 being exploited?

There is no known exploitation of CVE-2026-72783 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72783 and fix it if it is affected.

What it is: CVE-2026-72783 is a medium-severity path traversal vulnerability in craftcms cms, published on 11 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-72783 in the wild and no public exploit code.

Affected packages and fixed versions:
- craftcms/cms (Packagist): affected from 4.0.0-RC1; fixed in 4.18.2
- craftcms/cms (Packagist): affected from 4.0.0-RC1; fixed in 4.18.2
- craftcms/cms (Packagist): affected from 5.0.0-RC1; fixed in 5.10.6
- craftcms/cms (Packagist): affected from 5.0.0-RC1; fixed in 5.10.6

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-2026-72783/ (Markdown: https://insights.sbomify.com/CVE-2026-72783/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72783
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72783
- OSV: https://osv.dev/vulnerability/CVE-2026-72783

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72783/
Summaries are generated and may contain mistakes; the official description above is the record.