CVE-2021-41238
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedHangfire is an open source system to perform background job processing in a .NET or .NET Core applications. No Windows Service or separate process required. Dashboard UI in Hangfire.Core uses authorization filters to protect it from showing sensitive data to unauthorized users. By default when no custom authorization filters specified, `LocalRequestsOnlyAuthorizationFilter` filter is being used to allow only local requests and prohibit all the remote requests to provide sensible, protected by default settings. However due to the recent changes, in version 1.7.25 no authorization filters are used by default, allowing remote requests to succeed. If you are using `UseHangfireDashboard` method with default `DashboardOptions.Authorization` property value, then your installation is impacted. If any other authorization filter is specified in the `DashboardOptions.Authorization` property, the you are not impacted. Patched versions (1.7.26) are available both on Nuget.org and as a tagged release on the github repo. Default authorization rules now prohibit remote requests by default again by including the `LocalRequestsOnlyAuthorizationFilter` filter to the default settings. Please upgrade to the newest version in order to mitigate the issue. For users who are unable to upgrade it is possible to mitigate the issue by using the `LocalRequestsOnlyAuthorizationFilter` explicitly when configuring the Dashboard UI.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceHangfire.Core version 1.7.25 changed default authorization behavior for its Dashboard UI, removing the automatic application of LocalRequestsOnlyAuthorizationFilter. This allows remote, unauthenticated attackers to access the Dashboard and view sensitive background job data, schedule information, and potentially execute jobs depending on configuration.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 1.7.25CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check Hangfire.Core versionInspect the installed Hangfire.Core package version in your project references (packages.config, .csproj, or via dotnet list package). Compare it to the affected version 1.7.25.Affected if Hangfire.Core version is exactly 1.7.25 and no explicit authorization filter has been configured.
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Confirm Hangfire Dashboard is enabledSearch your codebase for app.UseHangfireDashboard() or OWIN startup configuration that enables the Dashboard. Without the Dashboard enabled, this vulnerability does not apply.Affected if The Dashboard is enabled in your application configuration.
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Inspect DashboardOptions.Authorization configurationLook for DashboardOptions with AuthorizationFilters, Authorization, or AuthorizationManager explicitly set in your UseHangfireDashboard call or configuration code. Check if LocalRequestsOnlyAuthorizationFilter or a custom authorization filter is explicitly added.Affected if No explicit authorization filter is configured and the application is using Hangfire.Core 1.7.25.
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Test remote access to Dashboard endpointFrom an external host (not localhost), attempt to access the Hangfire Dashboard URL (typically /hangfire or /dashboard). A successful unauthenticated response indicates the default permissive authorization is in effect.Affected if The Dashboard responds without requiring authentication from a non-localhost request.
You are affected if you are running Hangfire.Core version 1.7.25 and the Hangfire Dashboard is accessible without authentication from remote hosts because explicit authorization was not configured.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedUpgrade to Hangfire.Core version 1.7.26 or later to restore default authorization protections. Alternatively, explicitly configure LocalRequestsOnlyAuthorizationFilter in DashboardOptions.Authorization if upgrading is not feasible.
1.7.26
- Upgrade Hangfire.Core to version 1.7.26 or later using NuGet package manager (e.g., `Install-Package Hangfire.Core -Version 1.7.26` or `dotnet add package Hangfire.Core --version 1.7.26`).
- Verify the Dashboard is accessible only from localhost after the upgrade by attempting a remote request, which should now be denied by the default LocalRequestsOnlyAuthorizationFilter.
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation1.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-41238 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-41238 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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