CVE-2026-24899
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 · uneditedFleet is open source device management software. Prior to version 4.82.0, a vulnerability in Fleet's Windows MDM enrollment flow allows authentication tokens from any Azure AD tenant to be accepted. Because Fleet validates JWT signatures using Microsoft's multi-tenant JWKS endpoint but does not enforce the `aud` (audience) or `iss` (issuer) claims, any Microsoft-signed Azure AD access token containing the expected scopes can be used to authenticate to Fleet's MDM endpoints. If Windows MDM is enabled, an attacker with access to any Azure AD tenant can obtain a valid Microsoft-signed token and use it to enroll unauthorized devices and interact with Fleet's MDM management APIs. During device management, Fleet may expose sensitive enrollment secrets embedded in MDM command payloads, enabling further unauthorized access. Version 4.82.0 contains a patch. If an immediate upgrade is not possible, affected Fleet users should temporarily disable Windows MDM.
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 confidenceFleet's Windows MDM enrollment validates JWT signatures from Microsoft's multi-tenant JWKS endpoint but fails to enforce the `aud` and `iss` claims, accepting tokens from any Azure AD tenant. Attackers can obtain a Microsoft-signed token with required scopes and use it to enroll unauthorized devices or interact with MDM APIs, potentially exposing sensitive enrollment secrets in MDM command payloads.
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< 4.82.0CVSS 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 Fleet versionRun `fleetctl version` or access the Fleet UI and navigate to the About/Dashboard page to view the installed Fleet version numberAffected if The installed version is less than 4.82.0 (e.g., 4.81.0, 4.80.0, etc.)
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Verify Windows MDM enrollment is enabledUse the Fleet UI under Settings > MDM, or run `fleetctl get config` to examine the MDM configuration, or query the Fleet API endpoints related to MDM enrollment statusAffected if Windows MDM enrollment is actively enabled and configured for device enrollment
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Confirm MDM API endpoints are accessibleTest access to Fleet's MDM API endpoints (typically under /api/mdm) or check the MDM beta/settings page in the Fleet interfaceAffected if The Windows MDM feature is accessible and accepting enrollment requests
You are affected if your Fleet version is below 4.82.0 AND Windows MDM enrollment is enabled, because the missing aud/iss claim validation allows tokens from any Azure AD tenant to be accepted for enrollment.
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 · scoped4.82.0
Upgrade to Fleet v4.82.0 which adds proper `aud` and `iss` claim validation, or temporarily disable Windows MDM if immediate upgrade is not feasible.
4.82.0
- Upgrade Fleet to version 4.82.0 or later to apply the security patch
- After upgrading, verify that Windows MDM enrollment properly validates the `aud` and `iss` claims in Azure AD tokens
- If immediate upgrade is not possible, temporarily disable Windows MDM enrollment in Fleet settings as a mitigation
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA3.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2026-24899 — 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-2026-24899 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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