iOSOperating system · Cisco
CVE-1999-0293
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 · uneditedAAA authentication on Cisco systems allows attackers to execute commands without authorization.
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 confidenceThis is a historical vulnerability from 1999 affecting Cisco systems with AAA (Authentication, Authorization, and Accounting) configuration. The vulnerability allows remote attackers to bypass authentication and execute arbitrary commands without proper authorization, potentially gaining full administrative control over the affected Cisco device.
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
all versionsCVSS 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
- Authentication
- None
- Confidentiality
- Partial
- Integrity
- Partial
- Availability
- Partial
AV:N/AC:L/Au:N/C:P/I:P/A:P
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.
-
Confirm the device is running Cisco iOSUse the 'show version' command or check device documentation to identify the operating systemAffected if The device runs any version of Cisco iOS
-
Check if AAA is enabledUse the command 'show running-config | include aaa' or 'show aaa sessions' to see if AAA is configuredAffected if AAA (Authentication, Authorization, and Accounting) is enabled on the device
-
Review AAA authentication configurationUse 'show running-config | include aaa authentication' to display the configured AAA authentication methodsAffected if AAA authentication is configured with a method that allows bypass or fallback to vulnerable settings
-
Identify management interface exposureCheck the configuration for vty, console, and aux lines using 'show running-config | include line' and verify their AAA authentication bindingsAffected if Management interfaces (vty, console, aux) are configured to use AAA for authentication
-
Audit AAA method-list settingsReview the AAA method lists with 'show aaa method-lists' or examine the full AAA configuration sectionAffected if AAA method-lists are configured in a way that permits unauthenticated access
A user is affected if their Cisco iOS device has AAA enabled and the authentication configuration allows bypass of the configured authentication methods, potentially granting unauthorized administrative access.
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 dataIdentify and audit any legacy Cisco systems for proper AAA configuration, ensure AAA is correctly implemented with appropriate authentication methods, and apply any available Cisco IOS updates or security patches for legacy systems.
Fix this in iOS
Scoped from the published advisory
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-1999-0293 — 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-1999-0293 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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
- No spam, self-promotion, credentials, or personal data