CVE-2025-25006
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 · uneditedImproper handling of additional special element in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.
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 · moderate confidenceMicrosoft Exchange Server contains a vulnerability where improper handling of an additional special element allows an unauthenticated attacker to perform spoofing attacks over the network. This represents an input validation flaw that could enable attackers to masquerade as legitimate users or systems in email communications.
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= 2016= 2019< 15.02.2562.020CVSS 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
- None
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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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Identify Exchange Server versionOpen Exchange Management Shell and run: Get-ExchangeServer | Format-List Name, Edition, AdminDisplayVersion. Or check installed updates via Control Panel > Programs > View installed updates for Exchange security updates.Affected if The version is Exchange Server 2016 or 2019 (any build), or Exchange Server Subscription Edition with build number less than 15.02.2562.020
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Confirm internet-facing SMTP is enabledIn Exchange Management Shell, run: Get-ReceiveConnector to list all receive connectors. Identify connectors that accept external connections (typically Default Frontend connectors on port 25).Affected if The server has receive connectors configured to accept connections from external/unauthenticated sources on port 25 (default SMTP)
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Verify anonymous access permissions on receive connectorsIn Exchange Management Shell, run: Get-ReceiveConnector | Get-ADPermission | Where-Object {$_.User -like '*Anonymous*'}. This shows if anonymous users can access each connector.Affected if Anonymous users have permission on any receive connector that accepts external mail (indicating the server can receive unauthenticated email from the internet)
A user is affected if they run an affected Exchange version (2016, 2019, or Subscription Edition < 15.02.2562.020) AND have receive connectors accepting unauthenticated external SMTP connections, which is typical for Exchange servers that receive email from the internet.
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 · scoped15.02.2562.020
Apply Microsoft security updates for Exchange Server once released. Monitor Microsoft's Security Response Center for patch availability and deployment timeline.
Exchange Server Subscription Edition 15.02.2562.020 or later; Exchange Server 2016/2019 Cumulative Updates as specified in the corresponding security update KB
- Identify your current Microsoft Exchange Server version via Exchange Admin Center or Get-ExchangeServer cmdlet
- Review the Microsoft Security Response Center (msrc.microsoft.com) for CVE-2025-25006 and associated KB article
- Apply the security update corresponding to your Exchange version (KB500 line number varies by version)
- After patching, verify the update was successful by checking the Exchange version again
- Test critical email flow scenarios to ensure normal operation
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-25006 — 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-2025-25006 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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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data