dbcve.org
Ios XeOperating system · Cisco

CVE-2018-0160

MEDIUM · 6.3 CVSS v3.0 Published 2018-03-28
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
69/100
Remediation priority · Elevated
Remotely reachable 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
A vulnerability in Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper management of memory resources, referred to as a double free. An attacker could exploit this vulnerability by sending crafted SNMP packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. To exploit this vulnerability via SNMP Version 2c or earlier, the attacker must know the SNMP read-only community string for an affected system. To exploit this vulnerability via SNMP Version 3, the attacker must know the user credentials for the affected system. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS XE Software, have been configured to be queried over SNMP, and have Network Address Translation (NAT) enabled. Cisco Bug IDs: CSCve75818.

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

A double-free memory corruption vulnerability exists in the SNMP subsystem of Cisco IOS XE Software. An authenticated remote attacker with valid SNMP credentials (community string for v2c or user credentials for v3) can send crafted SNMP packets to cause memory corruption, forcing the affected device to reload and resulting in a denial of service. The vulnerability only affects devices with both SNMP configured and NAT enabled.

MitigationDisable SNMP if not required, otherwise migrate to SNMPv3 with authentication and encryption. If NAT is not needed on the affected device, disable it. Apply the vendor patch when available.

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
Affected:= 15.5\(3\)s

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
High
Privileges
Low
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:H/PR:L/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. Verify IOS XE version
    Execute 'show version' and locate the software version string. Look for a version exactly matching 15.5(3)s.
    Affected if The version string is exactly 15.5(3)s (this exact release is affected)
  2. Confirm SNMP is configured
    Run 'show running-config | include snmp' or 'show snmp' to check if any SNMP configuration exists (community strings for v2c or user configurations for v3).
    Affected if SNMP is actively configured with community strings or SNMPv3 users
  3. Confirm NAT is enabled
    Run 'show ip nat translations' or 'show running-config | include nat' to check for any NAT configuration or active translations.
    Affected if NAT is enabled and has active translations or configuration
  4. Check for SNMP and NAT coexistence
    Review the output from both checks above to confirm both features are present simultaneously on the same device.
    Affected if Both SNMP configuration AND NAT are simultaneously enabled on the device

A device is affected only if it runs IOS XE version 15.5(3)s AND has both SNMP and NAT enabled concurrently.

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

Disable SNMP if not required, otherwise migrate to SNMPv3 with authentication and encryption. If NAT is not needed on the affected device, disable it. Apply the vendor patch when available.

Fix this in Ios Xe Scoped from the published advisory
  • Consultation3.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,620
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,592.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-0160 — 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-2018-0160 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