How severe is CVE-2024-29035?

CVE-2024-29035 has a CVSS score of 4.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2024-29035?

CVE-2024-29035 affects the following packages: Umbraco.Cms.Core (NuGet), Umbraco.Cms.Web.BackOffice (NuGet). Ecosystems affected: NuGet.

How do I fix CVE-2024-29035?

Update Umbraco.Cms.Core to 13.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-29035 is resolved across your whole dependency graph.

How do I detect CVE-2024-29035 in my NuGet dependencies?

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

How do I mitigate CVE-2024-29035 if there is no patch (or I can't update yet)?

Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Is CVE-2024-29035 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-29035 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-2024-29035?

CVE-2024-29035 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 38th 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-2024-29035?

CVE-2024-29035 is classified as Server-Side Request Forgery (SSRF) (CWE-918). 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-2024-29035 published, and has it been updated?

CVE-2024-29035 was published on April 17, 2024 and was last updated on October 28, 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

.NET NuGet

Not in CISA KEV

MEDIUM severity

CVE-2024-29035 — Umbraco.Cms.Core

MEDIUMFix: umbraco/Umbraco-CMS@6b80678

CVE-2024-29035 is a medium-severity (CVSS 4.1) Server-Side Request Forgery (SSRF) vulnerability in Umbraco.Cms.Core. A fix is available for Umbraco.Cms.Core — see the affected versions and patch details below.

Umbraco's Blind SSRF Leads to Port Scan by using Webhooks

Also known asGHSA-74p6-39f2-23v3

Published

Apr 17, 2024

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 5, 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-2024-29035.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs38th percentile — riskier than 38% 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.Core.NETUmbraco.Cms.Web.BackOffice

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

Failing webhooks logs are available when solution is not in debug mode. Those logs can contain information that is critical.

Affected Versions

Umbraco versions 13.0.0 - 13.1.1

Patches

13.1.1

Workarounds

Disabling webhooks functionality.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`Umbraco.Cms.Core`	≥ 13.0.0&&< 13.1.1	13.1.1`dotnet add package Umbraco.Cms.Core --version 13.1.1`
.NETNuGet	`Umbraco.Cms.Web.BackOffice`	≥ 13.0.0&&< 13.1.1	13.1.1`dotnet add package Umbraco.Cms.Web.BackOffice --version 13.1.1`

Affected Products

1 product · 1 configurations

Application

umbraco cmsumbraco

≥ 13.0.0 && < 13.1.1

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.Cms.Core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Umbraco.Cms.Core to 13.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-29035 is resolved across your whole dependency graph.
Workarounds
Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Frequently Asked Questions

### Impact Failing webhooks logs are available when solution is not in debug mode. Those logs can contain information that is critical. ### Affected Versions Umbraco versions 13.0.0 - 13.1.1 ### Patches 13.1.1 ### Workarounds Disabling webhooks functionality.