CVE-2026-45501
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 · uneditedServer-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to perform spoofing over a network.
In the news
Third-party coverage- Microsoft June 2026 Patch Tuesday fixes 6 zero-days, 200 flaws
- Microsoft CVE Summary - Bleeping Computer
Surfaced from public web coverage — external links open in a new tab.
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 · low confidenceThis is a Server-Side Request Forgery (SSRF) vulnerability in Microsoft Exchange Server that allows an authenticated attacker to make the server perform arbitrary network requests, potentially enabling spoofing of internal resources and access to internal services that should not be exposed.
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< 15.02.2562.043CVSS 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
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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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Check Exchange Server versionRun Get-ExchangeServer or check Exchange Admin Center for installed version numberAffected if Version is 2016 or 2019, or Subscription Edition with build lower than 15.02.2562.043
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Identify Exchange editionConfirm whether the server is Standard or Datacenter edition of Subscription EditionAffected if Running Subscription Edition with build below 15.02.2562.043
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Verify network exposureReview firewall rules and network configuration to determine if Exchange web services are externally accessibleAffected if Exchange EWS, Autodiscover, or other web service endpoints are exposed to untrusted networks
You are affected if running Exchange Server 2016, 2019, or Subscription Edition with build below 15.02.2562.043 AND the server web services are network-accessible to attackers.
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 · scoped15.02.2562.043
Implement strict URL allowlisting and input validation for all endpoints that initiate outbound network requests; restrict Exchange server network egress to only trusted destinations.
Latest Cumulative Update for Exchange Server 2016/2019 that addresses CVE-2026-45501; Exchange Server Subscription Edition 15.02.2562.043 or later
- 1. Identify your current Exchange Server version by running Get-ExchangeServer | Format-List Name,Ad,ServerRole,Version in Exchange Management Shell
- 2. For Exchange Server 2016 and 2019: Upgrade to the latest available Cumulative Update (CU) that includes the security fix for CVE-2026-45501
- 3. For Exchange Server Subscription Edition: Update to version 15.02.2562.043 or later
- 4. Before applying updates, ensure you have a complete backup of Exchange databases and configuration
- 5. Test the update in a non-production environment first
- 6. Apply the update during a planned maintenance window
- 7. After installation, verify Exchange services are running properly using Get-Service MSExchange*
- 8. Review the Microsoft Security Response Center bulletin for any specific post-install configuration requirements
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation6.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,680.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45501 — 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-2026-45501 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