CVE-2021-3154
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 · uneditedAn issue was discovered in SolarWinds Serv-U before 15.2.2. Unauthenticated attackers can retrieve cleartext passwords via macro Injection. NOTE: this had a distinct fix relative to CVE-2020-35481.
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 confidenceA macro injection vulnerability in SolarWinds Serv-U (file transfer server) allows unauthenticated remote attackers to retrieve cleartext passwords. The flaw stems from improper input validation in the macro processing functionality, enabling attackers to inject malicious macros that expose stored credentials without authentication.
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< 15.2.2CVSS 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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Confirm SolarWinds Serv-U is installedCheck for Serv-U processes running (serv-u.exe or Serv-U.exe in Task Manager) or look for installation directory at C:\Program Files\SolarWinds\Serv-U or /opt/serv-u on LinuxAffected if Serv-U process or installation directory is found on the system
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Identify installed Serv-U versionCheck the version: On Windows, right-click serv-u.exe > Properties > Details tab, or run 'Serv-UAdmin.exe -v' from the installation directory. On Linux, run './serv-u -v' or check the version file in the installation directoryAffected if The installed version number is lower than 15.2.2
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Determine if Serv-U management interface is network-accessibleCheck if ports 80, 443, or 987 (typical Serv-U management ports) are listening on network interfaces accessible from outside localhost. Use 'netstat -an | findstr LISTENING' or 'ss -tlnp' to review listening portsAffected if Serv-U management ports are bound to non-localhost addresses (0.0.0.0 or external IP)
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Check for exposed Serv-U web interfaceIf a web interface is configured, attempt to access http(s)://<server>:987/ or the configured management URL from an external system to confirm accessibility. Review IIS or reverse proxy configurations if Serv-U is behind a web serverAffected if The Serv-U management interface is reachable without authentication from a remote system
A system is affected if SolarWinds Serv-U version 15.2.1 or earlier is installed and its management interface is network-accessible, allowing unauthenticated attackers to exploit the macro injection flaw.
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 data15.2.2
Upgrade SolarWinds Serv-U to version 15.2.2 or later. If immediate patching is not possible, restrict network access to the Serv-U management interfaces and implement additional authentication layers.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-3154 — 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-2021-3154 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