Identity Services EngineApplication · Cisco
CVE-2021-40123
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 web-based management interface of Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker with administrative read-only privileges to download files that should be restricted. This vulnerability is due to incorrect permissions settings on an affected device. An attacker could exploit this vulnerability by sending a crafted HTTP request to the device. A successful exploit could allow the attacker to download files that should be restricted.
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 confidenceCisco ISE contains a permissions misconfiguration in its web-based management interface that allows authenticated users with read-only administrative privileges to bypass intended access controls and download restricted files via crafted HTTP requests. The vulnerability stems from incorrect permission settings rather than a code flaw.
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
<= 2.6= 2.6.0= 2.7= 2.7\(0.207\)= 2.7\(0.356\)= 2.7\(0.903\)= 2.7.0= 3.0\(0.458\)= 3.0.0CVSS 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
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/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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Identify the installed Cisco ISE versionAccess the Cisco ISE admin web interface and navigate to Administration > System > Licensing, or use the CLI command 'show version' to determine the exact version numberAffected if The installed version matches any of these: <= 2.6, 2.6.0, 2.7, 2.7(0.207), 2.7(0.356), 2.7(0.903), 2.7.0, 3.0(0.458), 3.0.0
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Verify if read-only administrative accounts existReview the user account configuration in the Cisco ISE web interface under Administration > Identity Management > Identities > Users, or use the CLI command 'show running-configuration | include user' to list accounts with read-only privilegesAffected if One or more read-only administrative accounts are configured in Cisco ISE
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Confirm web-based management interface is accessibleAttempt to access the Cisco ISE admin portal through HTTPS to verify the web management interface is enabled and reachableAffected if The web-based management interface is accessible and accepts authentication
Your environment is affected if Cisco ISE is running an affected version AND the web-based management interface is accessible with read-only administrative accounts configured, allowing such users to potentially download restricted files via crafted HTTP requests.
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 dataApply Cisco's patch for CVE-2021-40123 and verify that read-only administrative accounts can no longer access restricted system files through the web interface.
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-2021-40123 — 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-2021-40123 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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