StarosOperating system · Cisco
CVE-2020-3602
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 · uneditedA vulnerability in the CLI of Cisco StarOS operating system for Cisco ASR 5000 Series Routers could allow an authenticated, local attacker to elevate privileges on an affected device. The vulnerability is due to insufficient input validation of CLI commands. An attacker could exploit this vulnerability by sending crafted commands to the CLI. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the root user on the affected device. To exploit this vulnerability, an attacker would need to have valid credentials on an affected device and know the password for the cli test-commands command.
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 · moderate confidenceA local privilege escalation vulnerability in Cisco StarOS CLI for ASR 5000 routers allows an authenticated attacker with knowledge of a specific command password to send crafted CLI commands that bypass input validation, executing arbitrary code with root privileges.
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
StarosOperating system
< 21.19.n4CVSS 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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:H/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 the system runs Cisco StarOSRun 'show version' or 'show system information' in the StarOS CLI to confirm the operating system and hardware platform (ASR 5000 series)Affected if The system is confirmed to be running Cisco StarOS on ASR 5000 hardware
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Determine the installed StarOS versionExecute 'show version' in the StarOS CLI and locate the StarOS version string in the outputAffected if The displayed StarOS version is lower than 21.19.n4 (for example, 21.18.x, 21.17.x, or earlier)
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Check if the cli test-commands mode is configuredIn StarOS CLI, attempt to enter 'test-commands' mode by typing 'test-commands' at the prompt and observe if a password is requested or if access is grantedAffected if The test-commands mode is accessible (password is either known, default, or not set)
A system is affected if it is a Cisco ASR 5000 running StarOS version below 21.19.n4 AND the cli test-commands feature is configured and accessible to an authenticated attacker.
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 data21.19.n4
Restrict CLI access to essential personnel only, change the cli test-commands password if known, and apply Cisco's available patches for StarOS.
Fix this in Staros
Scoped from the published advisory
- Consultation4.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,728.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-3602 — 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-2020-3602 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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