Identity Services EngineApplication · Cisco
CVE-2026-20180
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 Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have at least Read Only Admin credentials. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root. In single-node ISE deployments, successful exploitation of these vulnerabilities could cause the affected ISE node to become unavailable, resulting in a denial of service (DoS) condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.
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 command injection vulnerability in Cisco Identity Services Engine (ISE) allows authenticated attackers with Read Only Admin credentials to execute arbitrary OS commands via crafted HTTP requests due to insufficient input validation. Successful exploitation grants user-level access that can be escalated to root privileges, potentially causing DoS in single-node deployments.
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
Identity Services EngineApplication
< 3.2.0= 3.2.0= 3.3.0= 3.4.0CVSS 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
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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 installed Cisco ISE versionLog into the ISE admin UI and navigate to Administration > System > Licensing, or use the CLI command 'show version' to determine the exact version numberAffected if The installed version is < 3.2.0, = 3.2.0, = 3.3.0, or = 3.4.0
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Verify ISE web interface accessibilityConfirm that the ISE admin web interface (ports 443 or 8080) is reachable from network segments accessible to untrusted usersAffected if The web interface is exposed to networks with untrusted or unknown users
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Review admin user accountsNavigate to Administration > Identity Management > Identities > Users in the ISE admin UI to list all administrative accounts, particularly those with Read Only Admin privilegesAffected if Any Read Only Admin or higher-privilege accounts exist in the system
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Examine ISE logs for suspicious HTTP activityUse the ISE CLI to access logs via 'show logging application' or access logs via the ISE monitoring portal, looking for unusual or crafted HTTP requests to ISE interfacesAffected if Unusual HTTP requests are found in access logs, especially from Read Only Admin accounts
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Check for unexpected user-level processes or commandsAccess the ISE CLI and use 'show process cpu history' or 'show processes' to identify any unexpected user processes that may indicate command injection activityAffected if Unexpected processes or commands are running under non-system user accounts
You are affected if Cisco ISE version is < 3.2.0, = 3.2.0, = 3.3.0, or = 3.4.0 AND the web interface is accessible to authenticated users with Read Only Admin credentials.
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.
dbcve · scoped3.2.0
Apply Cisco's security patches for CVE-2026-20180 immediately, limit administrative access to trusted personnel only, and monitor for suspicious HTTP request patterns targeting ISE interfaces.
ISE version 3.4.1 or later (verify exact version from Cisco security advisory)
- Verify current Cisco ISE version by navigating to Administration > System > Licensing > Product Licensing in the ISE admin UI
- Review the Cisco ISE release notes and security advisories for CVE-2026-20180 to confirm the specific fixed version (expected to be 3.4.1 or later)
- Schedule a maintenance window for the upgrade, ensuring backup of ISE configuration
- Download the fixed ISE version from Cisco.com or your Cisco smart account
- Follow Cisco ISE upgrade documentation: ensure proper health checks, sufficient disk space, and valid licenses before initiating upgrade
- Perform the upgrade in a test/staging environment first if possible, or upgrade secondary nodes before primary in multi-node deployments
- After upgrade, verify system functionality and confirm the vulnerability is remediated
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Identity Services Engine
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-20180 — 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-2026-20180 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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