CVE-2026-26333
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 · uneditedCalero VeraSMART versions prior to 2022 R1 expose an unauthenticated .NET Remoting HTTP service on TCP port 8001. The service publishes default ObjectURIs (including EndeavorServer.rem and RemoteFileReceiver.rem) and permits the use of SOAP and binary formatters with TypeFilterLevel set to Full. An unauthenticated remote attacker can invoke the exposed remoting endpoints to perform arbitrary file read and write operations via the WebClient class. This allows retrieval of sensitive files such as WebRoot\\web.config, which may disclose IIS machineKey validation and decryption keys. An attacker can use these keys to generate a malicious ASP.NET ViewState payload and achieve remote code execution within the IIS application context. Additionally, supplying a UNC path can trigger outbound SMB authentication from the service account, potentially exposing NTLMv2 hashes for relay or offline cracking.
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 confidenceCalero VeraSMART versions prior to 2022 R1 expose an unauthenticated .NET Remoting HTTP service on TCP port 8001 with default ObjectURIs (EndeavorServer.rem and RemoteFileReceiver.rem) using SOAP and binary formatters with TypeFilterLevel=Full. Attackers can invoke these endpoints to perform arbitrary file read/write via WebClient, accessing sensitive files like web.config to extract IIS machineKey validation/decryption keys for malicious ViewState payload generation leading to IIS context RCE. UNC path inputs also trigger outbound SMB authentication exposing NTLMv2 hashes.
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< 2022.0= 2022.0CVSS 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
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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 Calero VeraSMART installation and versionLocate the VeraSMART installation directory (commonly under C:\Program Files\Calero or C:\Calero) and check the version information in the application files, or use Windows Programs and Features to find the installed version.Affected if The installed version is prior to 2022 R1 or equals 2022.0 (e.g., 2021.x, 2020.x, etc.)
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Verify TCP port 8001 is listeningRun 'netstat -an | findstr :8001' or use PowerShell 'Test-NetConnection -ComputerName localhost -Port 8001' to check if port 8001 is bound to a listening service.Affected if Port 8001 is in LISTENING state and accepting connections from your vantage point
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Confirm .NET Remoting endpoints are accessibleAttempt to access the known ObjectURIs: http://target:8001/EndeavorServer.rem and http://target:8001/RemoteFileReceiver.rem using a web request tool or check if these respond to HTTP requests.Affected if Either endpoint returns a response indicating the .NET Remoting service is exposed (even an error response confirms the service is reachable)
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Check network exposure of port 8001Review firewall rules or perform an external port scan from an untrusted network segment to determine if TCP port 8001 is accessible from outside the trusted network.Affected if Port 8001 is reachable from untrusted network segments or the internet
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Inspect for sensitive file accessibilityIf the service is exposed, attempt to access web.config via the RemoteFileReceiver endpoint or check if UNC path inputs can trigger outbound SMB connections (monitor network for SMB to external hosts).Affected if Arbitrary file read is possible via the exposed endpoints or outbound SMB connections are observed to untrusted destinations
A defender is affected if Calero VeraSMART version 2022.0 or earlier is installed AND TCP port 8001 is accessible from any network where untrusted actors could reach it, allowing potential file access or NTLMv2 hash capture.
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 · scoped2022.0
Upgrade Calero VeraSMART to version 2022 R1 or later. Additionally, block TCP port 8001 from untrusted networks via firewall, rotate any exposed machineKey values, and reset service account credentials if NTLMv2 hash exposure is suspected.
VeraSMART 2022 R1 or later
- 1. Identify all Calero VeraSMART instances currently deployed and confirm their exact version numbers
- 2. If running version 2022.0 or earlier, plan for upgrade to version 2022 R1 or later
- 3. Before upgrading in production, test the new version in a staging environment to verify functionality
- 4. Schedule maintenance window for upgrade procedure
- 5. Perform full backup of the VeraSMART database and configuration files
- 6. Execute upgrade to VeraSMART 2022 R1 or latest stable release following vendor documentation
- 7. After upgrade, verify that the .NET Remoting service on TCP port 8001 is either disabled or properly authenticated
- 8. Confirm that the EndeavorServer.rem and RemoteFileReceiver.rem endpoints are no longer exposed without authentication
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
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-26333 — 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-2026-26333 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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