dbcve.org
iOSOperating system · Cisco

CVE-2016-6379

HIGH · 7.5 CVSS v3.0 Published 2016-10-05
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

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 · unedited
Cisco IOS 12.2 and IOS XE 3.14 through 3.16 and 16.1 allow remote attackers to cause a denial of service (device reload) via crafted IP Detail Record (IPDR) packets, aka Bug ID CSCuu35089.

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 confidence

A denial of service vulnerability exists in Cisco IOS 12.2 and IOS XE versions 3.14 through 3.16 and 16.1 where the device reloads upon processing specially crafted IP Detail Record (IPDR) packets. The vulnerability stems from insufficient validation of IPDR packet data during parsing, allowing remote attackers to trigger a device reload without authentication.

MitigationUpgrade Cisco IOS/IOS XE to a patched version beyond 16.1. If immediate patching is not feasible, consider network segmentation to limit exposure of affected devices to untrusted networks.

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
Affected:= 12.2\(33\)cx= 12.2\(33\)cy= 12.2\(33\)cy1= 12.2\(33\)sch= 12.2\(33\)sch0a= 12.2\(33\)sch1= 12.2\(33\)sch2= 12.2\(33\)sch2a= 12.2\(33\)sch3= 12.2\(33\)sch4= 12.2\(33\)sch5= 12.2\(33\)sch6
Ios XeOperating system
Affected:= 3.14.0s= 3.14.1s= 3.14.2s= 3.14.3s= 3.14.4s= 3.15.0s= 3.15.1cs= 3.15.1s= 3.15.2s= 3.15.3s= 3.15.4s= 3.16.0cs

CVSS 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
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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 checks

Work through these to decide whether this CVE applies to you.

  1. Determine the installed Cisco IOS or IOS XE version
    Execute 'show version' on the device CLI and locate the version string in the output (e.g., 'Version 15.5(3)T' or 'IOS XE Version 03.14.01S')
    Affected if The version matches any of the following: Cisco iOS 12.2(33)cx, 12.2(33)cy, 12.2(33)cy1, 12.2(33)sch, 12.2(33)sch0a, 12.2(33)sch1, 12.2(33)sch2, 12.2(33)sch2a, 12.2(33)sch3, 12.2(33)sch4, 12.2(33)sch5, 12.2(33)sch6; or IOS XE 3.14.0S, 3.14.1S, 3.14.2S, 3.14.3S, 3.14.4S, 3.15.0S, 3.15.1CS, 3.15.1S, 3
  2. Verify whether the IPDR feature is enabled on the device
    Execute 'show running-config | include ipdr' or 'show ipdr' if the command is supported, to check for any IPDR-related configuration lines
    Affected if IPDR configuration exists and the feature is actively enabled on one or more interfaces or processes
  3. Confirm the device is reachable from untrusted networks
    Review interface configurations and access control lists using 'show ip interface brief' and check if the device accepts IPDR traffic (typically UDP port 4000 or similar) from external or untrusted sources
    Affected if The device has IPDR enabled and is exposed to network segments where untrusted or anonymous users can send packets to the device

The device is affected if it runs any of the specific IOS 12.2(33) variants or IOS XE versions 3.14.0S through 3.16.0CS, has IPDR feature configured, and can receive crafted IPDR packets from accessible network paths.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade Cisco IOS/IOS XE to a patched version beyond 16.1. If immediate patching is not feasible, consider network segmentation to limit exposure of affected devices to untrusted networks.

Fix this in iOS Scoped from the published advisory
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,180
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,488.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-6379 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2016-6379 in production — separate from our analysis above.

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.

What this is

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.

What belongs here
  • 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