CVE-2025-66265
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 · uneditedCMService.exe creates the C:\\usr directory and subdirectories with insecure permissions, granting write access to all authenticated users. This allows attackers to replace configuration files (such as snmp.conf) or hijack DLLs to escalate privileges.
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 confidenceCMService.exe creates the C:\usr directory and subdirectories with insecure permissions, granting write access to all authenticated users. This allows local attackers to replace configuration files (such as snmp.conf) or plant malicious DLLs to achieve privilege escalation to SYSTEM.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- Authentication
- X
- User interaction
- None
- Scope
- X
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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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Locate CMService.exe on the systemSearch for CMService.exe using: Get-ChildItem -Path C:\ -Recurse -Filter CMService.exe -ErrorAction SilentlyContinue or check common installation paths like C:\Program Files\, C:\Program Files (x86)\, or the application's install directoryAffected if CMService.exe is found and running on the system
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Verify C:\usr directory existsCheck if the directory exists using: Test-Path C:\usr or dir C:\usrAffected if C:\usr directory exists on the system (created by CMService.exe)
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Inspect permissions on C:\usrRun: icacls C:\usr to view ACLs. Look for entries showing authenticated users or Users group with (F) Full or (W) Write permissionsAffected if Authenticated Users or Users group has Write or Full control permissions to C:\usr
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Inspect permissions on C:\usr subdirectoriesRun: icacls C:\usr\* /T to recursively view ACLs on all subdirectories. Check each entry for write permissions granted to authenticated usersAffected if Any subdirectory under C:\usr grants Write or Full control to authenticated users
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Check for replaceable configuration filesSearch for configuration files in C:\usr and subdirectories, especially snmp.conf: Get-ChildItem -Path C:\usr -Recurse -Filter *.conf -ErrorAction SilentlyContinueAffected if Configuration files like snmp.conf exist in C:\usr or its subdirectories with world-writable permissions
If CMService.exe is installed and C:\usr with its subdirectories grant Write or Full permissions to authenticated users, the system is vulnerable to privilege escalation via file replacement.
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.
From vendor dataRestrict permissions on C:\usr and its subdirectories to remove write access for authenticated users, limiting access to administrators or the service account only.
- Consultation2.0 h
- Implementation2.0 h
- Testing1.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-66265 — 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-2025-66265 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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- 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