iOSOperating system · Cisco
CVE-2019-12648
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 IOx application environment for Cisco IOS Software could allow an authenticated, remote attacker to gain unauthorized access to the Guest Operating System (Guest OS) running on an affected device. The vulnerability is due to incorrect role-based access control (RBAC) evaluation when a low-privileged user requests access to a Guest OS that should be restricted to administrative accounts. An attacker could exploit this vulnerability by authenticating to the Guest OS by using the low-privileged-user credentials. An exploit could allow the attacker to gain unauthorized access to the Guest OS as a root user.
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 vulnerability in Cisco IOS Software's IOx application environment allows low-privileged users to bypass role-based access control (RBAC) checks and gain unauthorized root access to the Guest Operating System. The flaw permits an authenticated remote attacker to escalate privileges by authenticating with standard user credentials to a Guest OS that should be restricted to administrative accounts.
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
iOSOperating system
= 15.7\(3\)m3CVSS 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
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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 Cisco IOS versionExecute 'show version' or 'show ios version' on the Cisco device to retrieve the installed IOS version.Affected if The version displayed is exactly 15.7(3)m3.
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Verify IOx application environment is enabledExecute 'show iox' or 'show app-hosting details' to check if the IOx feature is active on the device.Affected if IOx is enabled and running on the device.
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Confirm Guest OS instances are configuredExecute 'show guestshell' or 'show app-hosting list' to list any Guest Operating Systems or application containers deployed on the device.Affected if One or more Guest OS instances are configured and running.
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Review user account RBAC assignmentsExecute 'show users' and 'show privilege' to identify authenticated users and their privilege levels. Check 'show running-config | include username' to review user account configurations.Affected if Standard (non-administrator) user accounts exist with access to IOx or Guest OS functionality.
The environment is affected if the Cisco IOS version is exactly 15.7(3)m3, IOx is enabled, Guest OS instances are running, and low-privileged user accounts have access to IOx features.
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 the relevant Cisco IOS Software security update that corrects the RBAC evaluation logic. Until patched, restrict low-privileged user accounts from accessing IOx/Guest OS features and monitor for unauthorized access attempts.
Fix this in iOS
Scoped from the published advisory
- Consultation6.0 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 $7,680.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2019-12648 — 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-2019-12648 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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