How severe is CVE-2026-24687?

No CVSS score has been assigned to CVE-2026-24687 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-24687?

CVE-2026-24687 affects the following packages: Umbraco.Forms (NuGet), Umbraco.Forms (NuGet). Ecosystems affected: NuGet.

How do I fix CVE-2026-24687?

Update Umbraco.Forms to 16.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24687 is resolved across your whole dependency graph.

How do I detect CVE-2026-24687 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Umbraco.Forms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-24687 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2026-24687 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-24687 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-24687?

CVE-2026-24687 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 40th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-24687?

CVE-2026-24687 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-24687 published, and has it been updated?

CVE-2026-24687 was published on January 30, 2026 and was last updated on February 3, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET NuGet

Not in CISA KEV

CVE-2026-24687 — Umbraco.Forms

CVE-2026-24687 is a Path Traversal vulnerability in Umbraco.Forms. A fix is available for Umbraco.Forms — see the affected versions and patch details below.

Umbraco.Forms has Path Traversal and File Enumeration Vulnerabilities in Linux/Mac

Published

Jan 30, 2026

Updated

Feb 3, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

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 CVE-2026-24687.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs40th percentile — riskier than 40% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

2 pkgs affected

.NETUmbraco.Forms.NETUmbraco.Forms

Real-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

Impact

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.

Patches

This issue affects versions 16 and 17 of Umbraco Forms and is patched in 16.4.1 and 17.1.1

Workarounds

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
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.

References

Credit to Kevin Joensen from Baldur Security for finding this vulnerability

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`Umbraco.Forms`	≥ 16.0.0&&< 16.4.1	16.4.1`dotnet add package Umbraco.Forms --version 16.4.1`
.NETNuGet	`Umbraco.Forms`	≥ 17.0.0&&< 17.1.1	17.1.1`dotnet add package Umbraco.Forms --version 17.1.1`

Affected Products

1 product · 2 configurations

Application

umbraco formsumbraco

≥ 17.0.0 && < 17.1.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Umbraco.Forms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Umbraco.Forms to 16.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24687 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

### Impact 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. ### Patches This issue affects versions 16 and 17 of Umbraco Forms and is patched in 16.4.1 and 17.1.1 ### Workarounds 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 `file

O3 Security · Impact-Aware SCA

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CVE-2026-24687 — Umbraco.Forms

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

Real-World Exposure

Description

Impact

Patches

Workarounds

References

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2026-24687 in your dependencies?