CVE-2023-49089
HIGHCVE-2023-49089 is a high-severity (CVSS 7.7) Path Traversal vulnerability in Umbraco.CMS. O3 Security confirms whether CVE-2023-49089 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Umbraco CMS possible path traversal when creating packages from backoffice
Blast Radius
Umbraco.CMS.NETUmbraco.CMS.NETUmbraco.CMSReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.0, Backoffice users with permissions to create packages can use path traversal and thereby write outside of the expected location. Versions 8.18.10, 10.8.1, and 12.3.0 contain a patch for this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | Umbraco.CMS | ≥ 8.0.0&&< 8.18.10 | 8.18.10 |
| .NETNuGet | Umbraco.CMS | ≥ 9.0.0&&< 10.8.1 | 10.8.1 |
| .NETNuGet | Umbraco.CMS | ≥ 11.0.0&&< 12.3.4 | 12.3.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Umbraco.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 Umbraco.CMS to 8.18.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-49089 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 CVE-2023-49089 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 CVE-2023-49089. 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-2023-49089 in your dependencies?
O3 detects CVE-2023-49089 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.