Security ManagerApplication · Cisco
CVE-2020-27131
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 · uneditedMultiple vulnerabilities in the Java deserialization function that is used by Cisco Security Manager could allow an unauthenticated, remote attacker to execute arbitrary commands on an affected device. These vulnerabilities are due to insecure deserialization of user-supplied content by the affected software. An attacker could exploit these vulnerabilities by sending a malicious serialized Java object to a specific listener on an affected system. A successful exploit could allow the attacker to execute arbitrary commands on the device with the privileges of NT AUTHORITY\SYSTEM on the Windows target host. Cisco has not released software updates that address these vulnerabilities.
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 confidenceCritical Java deserialization vulnerabilities in Cisco Security Manager allow unauthenticated remote attackers to execute arbitrary commands with NT AUTHORITY\SYSTEM privileges by sending malicious serialized Java objects to specific listeners. The root cause is insecure deserialization of user-supplied content without proper validation or safelist controls.
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
Security ManagerApplication
<= 4.22CVSS 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 if Cisco Security Manager is installedReview installed applications on Windows systems or check for Cisco Security Manager installation directories. Look for folders named 'Cisco' or 'Security Manager' in Program Files.Affected if Cisco Security Manager is present on the system
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Determine installed version of Cisco Security ManagerCheck the application's About or Version information within the Cisco Security Manager GUI, or look for version files in the installation directory. Compare the version number to the affected range (4.22 and below).Affected if Installed version is 4.22 or lower
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Identify exposed listeners accepting network connectionsReview network listener configurations within Cisco Security Manager. Check which ports and interfaces the application is bound to listen on for incoming connections.Affected if Any listener ports are open and accessible from network
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Verify if listeners accept deserialized Java objectsExamine the listener service configurations to confirm they handle serialized Java content. The vulnerability exists in listeners that accept user-supplied serialized Java objects.Affected if Listeners accept serialized Java object input without validation
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Assess network accessibility of affected listenersDetermine if the exposed listener ports are reachable from untrusted networks. Use netstat or port scanning tools to identify listening ports and verify network exposure.Affected if Listener ports are accessible from outside the trusted network
If Cisco Security Manager version 4.22 or lower is installed with exposed listeners that accept serialized Java input, the system is vulnerable to remote command execution as NT AUTHORITY\SYSTEM.
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 dataSince no vendor patch is available, implement compensating controls including network segmentation to restrict access to affected listeners, deploy WAF/IPS rules to block known malicious Java deserialization patterns, and consider implementing a Java deserialization safelist filter at the network boundary.
Fix this in Security Manager
Scoped from the published advisory
- Consultation8.0 h
- Implementation24.0 h
- Testing12.0 h
- Review / QA8.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $14,656.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-27131 — 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-2020-27131 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
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