Ios XeOperating system · Cisco
CVE-2017-3824
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 handling of list headers in Cisco cBR Series Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Cisco cBR-8 Converged Broadband Routers running vulnerable versions of Cisco IOS XE are affected. More Information: CSCux40637. Known Affected Releases: 15.5(3)S 15.6(1)S. Known Fixed Releases: 15.5(3)S2 15.6(1)S1 15.6(2)S 15.6(2)SP 16.4(1).
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 the handling of list headers in Cisco cBR-8 Converged Broadband Routers running Cisco IOS XE allows an unauthenticated remote attacker to send malicious packets that cause the device to reload, resulting in denial of service.
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
Ios XeOperating system
= 3.16.0= 3.16.1= 3.17.0CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/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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Confirm Cisco cBR-8 hardwareExecute 'show version' and look for 'cBR-8' or 'Converged Broadband Router' in the hardware descriptionAffected if Device is not a Cisco cBR-8 router - not affected
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Confirm Cisco IOS XE softwareExecute 'show version' and verify the software is listed as IOS XE (not classic IOS)Affected if Device does not run Cisco IOS XE - not affected
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Check IOS XE version numberExecute 'show version' and locate the IOS XE version string (typically shown as 'Version 16.x.x' or 'IOS XE 16.x.x'). Compare against the affected versions: 3.16.0, 3.16.1, or 3.17.0Affected if IOS XE version is exactly 3.16.0, 3.16.1, or 3.17.0 - device is affected
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Verify list header processing is enabledThis vulnerability is triggered by receiving malformed list header packets on any enabled interface. Check that interfaces are in 'up' state with 'show ip interface brief'Affected if Interfaces are administratively up and processing traffic - device can be exploited
A Cisco cBR-8 router running Cisco IOS XE version 3.16.0, 3.16.1, or 3.17.0 with active network interfaces is vulnerable to remote denial of service via malformed list header packets.
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 dataUpgrade Cisco IOS XE on cBR-8 routers to a fixed release (15.5(3)S2, 15.6(1)S1, 15.6(2)S, 15.6(2)SP, 16.4(1), or later).
Fix this in Ios Xe
Scoped from the published advisory
- Consultation3.0 h
- Implementation2.0 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 $2,304.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2017-3824 — 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-2017-3824 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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