How severe is GHSA-hmg4-wwm5-p999?

GHSA-hmg4-wwm5-p999 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-hmg4-wwm5-p999?

GHSA-hmg4-wwm5-p999 affects the following packages: Umbraco.Cms (NuGet), Umbraco.Cms (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-hmg4-wwm5-p999?

Update Umbraco.Cms to 14.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hmg4-wwm5-p999 is resolved across your whole dependency graph.

How do I detect GHSA-hmg4-wwm5-p999 in my NuGet dependencies?

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

How do I mitigate GHSA-hmg4-wwm5-p999 if there is no patch (or I can't update yet)?

Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Is GHSA-hmg4-wwm5-p999 actively exploited in the wild?

No public exploit code has been indexed for GHSA-hmg4-wwm5-p999 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 GHSA-hmg4-wwm5-p999?

GHSA-hmg4-wwm5-p999 has an EPSS (Exploit Prediction Scoring System) score of 1.6%, placing it in the 76th 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 GHSA-hmg4-wwm5-p999?

GHSA-hmg4-wwm5-p999 is classified as Information Exposure (CWE-200), CWE-203 (CWE-203). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-hmg4-wwm5-p999 published, and has it been updated?

GHSA-hmg4-wwm5-p999 was published on January 21, 2025 and was last updated on April 17, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET

.NET NuGet

Not in CISA KEV

MEDIUM severity

Umbraco Allows User Enumeration Feasible Based On Management API Timing and Response CodesGHSA-hmg4-wwm5-p999

MEDIUMFix: umbraco/Umbraco-CMS@559c6c9

GHSA-hmg4-wwm5-p999 is a medium-severity (CVSS 5.3) Information Exposure vulnerability in Umbraco.Cms. A fix is available for Umbraco.Cms — see the affected versions and patch details below.

Also known asCVE-2025-24011

Published

Jan 21, 2025

Updated

Apr 17, 2025

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 11, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
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 GHSA-hmg4-wwm5-p999.

EPSS Exploitation Probability

via FIRST.org ↗

1.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs76th percentile — riskier than 76% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

2 pkgs affected

.NETUmbraco.Cms.NETUmbraco.Cms

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

Umbraco is a free and open source .NET content management system. Starting in version 14.0.0 and prior to versions 14.3.2 and 15.1.2, it's possible to determine whether an account exists based on an analysis of response codes and timing of Umbraco management API responses. Versions 14.3.2 and 15.1.2 contain a patch. No known workarounds are available.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`Umbraco.Cms`	≥ 14.0.0&&< 14.3.2	14.3.2`dotnet add package Umbraco.Cms --version 14.3.2`
.NETNuGet	`Umbraco.Cms`	≥ 15.0.0&&< 15.1.2	15.1.2`dotnet add package Umbraco.Cms --version 15.1.2`

Affected Products

1 product · 2 configurations

Application

umbraco cmsumbraco

≥ 15.0.0 && < 15.1.2

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.Cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Umbraco.Cms to 14.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hmg4-wwm5-p999 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Frequently Asked Questions

### Impact Based on an analysis of response codes and timing of Umbraco 14+ management API responses, it's possible to determine whether an account exists. ### Patches Patched in 14.3.2 and 15.1.2. ### Workarounds None available.