CVE-2021-20108
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 · uneditedManage Engine Asset Explorer Agent 1.0.34 listens on port 9000 for incoming commands over HTTPS from Manage Engine Server. The HTTPS certificates are not verified which allows any arbitrary user on the network to send commands over port 9000. While these commands may not be executed (due to authtoken validation), the Asset Explorer agent will reach out to the manage engine server for an HTTP request. During this process, AEAgent.cpp allocates 0x66 bytes using "malloc". This memory is never free-ed in the program, causing a memory leak. Additionally, the instruction sent to aeagent (ie: NEWSCAN, DELTASCAN, etc) is converted to a unicode string, but is never freed. These memory leaks allow a remote attacker to exploit a Denial of Service scenario through repetitively sending these commands to an agent and eventually crashing it the agent due to an out-of-memory condition.
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 confidenceManage Engine Asset Explorer Agent 1.0.34 listens on port 9000 for HTTPS commands without verifying certificates, allowing any network user to send commands. The agent has memory leaks where AEAgent.cpp allocates 0x66 bytes via malloc and instruction strings converted to Unicode are never freed, enabling remote attackers to crash the agent via repeated commands causing an out-of-memory condition.
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= 1.0.34CVSS 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
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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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Verify Asset Explorer Agent installationLocate the ManageEngine Asset Explorer Agent on the system. Common installation paths include C:\Program Files\ManageEngine\AssetExplorer\Agent or similar. Check program files directory or use 'Get-ItemProperty' in PowerShell for installed software.Affected if The ManageEngine Asset Explorer Agent software is installed on the system.
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Confirm agent version is 1.0.34Check the exact version of the installed Asset Explorer Agent. Right-click the AEAgent.exe file, select Properties, and view the Version tab. Alternatively, run 'wmic product get name,version' or check the Windows registry under HKLM\SOFTWARE\ManageEngine or the installation directory for version info.Affected if The installed version is exactly 1.0.34.
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Detect if port 9000 is listeningRun 'netstat -an | findstr :9000' or 'Get-NetTCPConnection -LocalPort 9000' in PowerShell to check if the agent is listening on port 9000. Also verify the AEAgent.exe process is running via Task Manager or 'Get-Process AEAgent'.Affected if Port 9000 is in LISTENING state and the AEAgent process is active.
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Check HTTPS certificate validation on port 9000Use a tool like OpenSSL to connect to localhost:9000 and examine the certificate chain. Run 'openssl s_client -connect localhost:9000' and check if certificate verification fails or if no certificate is presented. Compare behavior with a properly configured HTTPS endpoint.Affected if The agent accepts connections on port 9000 without validating or requiring a trusted certificate.
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Identify memory leak symptomsMonitor the AEAgent.exe process for increasing memory usage over time. Check Windows Event Viewer under Application logs for frequent AEAgent crashes or out-of-memory events. Use Performance Monitor to track the Working Set memory of the agent process during repeated operations.Affected if The AEAgent.exe process exhibits continuously growing memory consumption or crashes with out-of-memory errors after receiving repeated commands.
A system is affected if ManageEngine Asset Explorer Agent version 1.0.34 is installed with port 9000 open and accepting HTTPS connections without proper certificate validation, especially if the agent shows memory growth or crash patterns consistent with the described memory leaks.
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 dataImplement HTTPS certificate verification on port 9000 and fix memory leaks by ensuring all allocated memory (both the 0x66 buffer and Unicode-converted instruction strings) are properly freed after use.
- Consultation4.0 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 $7,040.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-20108 — 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-2021-20108 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
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