dbcve.org
iOSOperating system · Cisco

CVE-2017-3862

HIGH · 8.6 CVSS v3.0 Published 2017-04-20
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
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
Multiple vulnerabilities in the EnergyWise module of Cisco IOS (12.2 and 15.0 through 15.6) and Cisco IOS XE (3.2 through 3.18) could allow an unauthenticated, remote attacker to cause a buffer overflow condition or a reload of an affected device, leading to a denial of service (DoS) condition. These vulnerabilities are due to improper parsing of crafted EnergyWise packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted EnergyWise packets to be processed by an affected device. An exploit could allow the attacker to cause a buffer overflow condition or a reload of the affected device, leading to a DoS condition. Cisco IOS Software and Cisco IOS XE Software support EnergyWise for IPv4 communication. Only IPv4 packets destined to a device configured as an EnergyWise domain member can trigger these vulnerabilities. IPv6 packets cannot be used to trigger these vulnerabilities. Cisco Bug ID CSCuu76493.

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 confidence

Multiple vulnerabilities in the EnergyWise module of Cisco IOS and IOS XE allow unauthenticated remote attackers to cause buffer overflows or device reloads via crafted EnergyWise packets. Only IPv4 packets destined to devices configured as EnergyWise domain members can trigger these vulnerabilities; IPv6 is not affected.

MitigationApply Cisco security updates for the relevant IOS/IOS XE versions. If patching is not immediately feasible, consider disabling EnergyWise on affected devices or implementing network segmentation to limit exposure 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\(33\)sxi4= 12.2\(33\)sxi4a= 12.2\(33\)sxi5= 12.2\(33\)sxi6= 12.2\(33\)sxi7= 12.2\(33\)sxi8= 12.2\(33\)sxi8a= 12.2\(33\)sxi9= 12.2\(33\)sxi10= 12.2\(33\)sxi11= 12.2\(33\)sxi12= 12.2\(33\)sxi13
Ios XeOperating system
Affected:= 3.2.1sg= 3.2.8sg= 3.3.1sg= 3.3.1sq= 3.4.1sg= 3.4.2sg= 3.4.3sg= 3.4.6sg= 3.4.8sg= 3.5.1e= 3.5.3e= 3.6.0e

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
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:L/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 checks

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

  1. Identify the IOS or IOS XE version
    Run 'show version' on the device CLI to retrieve the installed software version. Look for the release number in the format 12.2(XX) or 3.X.X.
    Affected if The version matches one of the affected releases listed: iOS 12.2(33)sxi4 through sxi13, or IOS XE 3.2.1sg through 3.6.0e.
  2. Verify if EnergyWise is enabled
    Run 'show energywise' or 'show energywise summary' to check whether the EnergyWise module is active on the device.
    Affected if EnergyWise is listed as enabled or running on the device.
  3. Confirm EnergyWise domain membership
    Run 'show energywise domain' to see if the device is configured as a member of an EnergyWise domain.
    Affected if The device shows as a member of an EnergyWise domain (domain name and role are displayed).

A device is affected if it runs a vulnerable iOS or IOS XE version from the listed ranges AND has EnergyWise enabled AND is configured as an EnergyWise domain member, as the vulnerability is triggered only by crafted IPv4 packets sent to domain members.

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

Apply Cisco security updates for the relevant IOS/IOS XE versions. If patching is not immediately feasible, consider disabling EnergyWise on affected devices or implementing network segmentation to limit exposure to untrusted networks.

Fix this in iOS Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
27.0 hours of engineering $4,800
Get help mitigating

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 locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-3862 — 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-2017-3862 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