Ios XeOperating system · Cisco

CVE-2013-1164

HIGH · 7.8 CVSS v2.0 Published 2013-04-11

Mitigation only

No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.

See remediation →

87/100

Remediation priority · High

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

Cisco IOS XE 3.4 before 3.4.4S, 3.5, and 3.6 on 1000 series Aggregation Services Routers (ASR) does not properly implement the Cisco Multicast Leaf Recycle Elimination (MLRE) feature, which allows remote attackers to cause a denial of service (card reload) via fragmented IPv6 multicast packets, aka Bug ID CSCtz97563.

Technical summary

dbcve analysis · moderate confidence

The vulnerability exists in the Cisco Multicast Leaf Recycle Elimination (MLRE) feature on ASR 1000 series routers running IOS XE versions 3.4 (prior to 3.4.4S), 3.5, and 3.6. The improper implementation of MLRE allows remote attackers to send specially crafted fragmented IPv6 multicast packets, triggering a denial of service via forced card reload.

MitigationUpgrade Cisco IOS XE to version 3.4.4S or later which contains the fix for this vulnerability. If immediate upgrade is not feasible, consider implementing edge filtering or rate-limiting for fragmented IPv6 multicast traffic as a temporary compensating control.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions

NVD · CPE data

Ios XeOperating system

Affected:= 3.4.0as= 3.4.0s= 3.4.1s= 3.4.2s= 3.4.3s= 3.5.0s= 3.6.0s

Asr 1001Hardware / appliance

Affected:all versions

Asr 1002Hardware / appliance

Affected:all versions

Asr 1002 XHardware / appliance

Affected:all versions

Asr 1004Hardware / appliance

Affected:all versions

Asr 1006Hardware / appliance

Affected:all versions

Asr 1013Hardware / appliance

Affected:all versions

CVSS breakdown

From the vector

Attack vector: Network
Complexity: Low
Authentication: None
Confidentiality: None
Integrity: None
Availability: Complete

AV:N/AC:L/Au:N/C:N/I:N/A:C

Am I affected?

dbcve checks

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

Identify the ASR 1000 series model

Run 'show version' or 'show inventory' to confirm the device is a Cisco ASR 1001, 1002, 1002-X, 1004, 1006, or 1013

Affected if The device is any ASR 1000 series model listed in the affected products
Check the IOS XE version

Run 'show version' and locate the IOS XE version string (for example, 3.4.0S, 3.5.0S, 3.6.0S)

Affected if Version is 3.4.0S through 3.4.3S, 3.5.0S, or 3.6.0S (versions prior to 3.4.4S in the 3.4 train)
Verify MLRE feature is enabled

Run 'show running-config | include mlre' or check for 'multicast leaf-recycle elimination' under the appropriate interface or global multicast configuration

Affected if MLRE feature is configured and active on the device
Confirm IPv6 multicast is active

Run 'show ipv6 multicast' or 'show ip mroute vrf * ipv6' to verify IPv6 multicast routing is enabled

Affected if IPv6 multicast routing or forwarding is enabled on the device

The device is vulnerable if it is an ASR 1000 series running an affected IOS XE version (3.4.x prior to 3.4.4S, 3.5.x, or 3.6.x) with the MLRE feature enabled and IPv6 multicast traffic processing active.

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

Remediation

From vendor data

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Upgrade Cisco IOS XE to version 3.4.4S or later which contains the fix for this vulnerability. If immediate upgrade is not feasible, consider implementing edge filtering or rate-limiting for fragmented IPv6 multicast traffic as a temporary compensating control.

Fix this in Ios Xe Scoped from the published advisory

Consultation3.0 h
Implementation4.0 h
Testing3.0 h
Review / QA2.0 h

12.0 hours of engineering $2,130

Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

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References

Primary sources

tools.cisco.comVendor Advisory
nvd.nist.govNVD record

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2013-1164 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2013-1164?

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.

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

At a glance

A fix existsA vendor remedy is published

Severity 7.8 High

Exploit likelihood EPSS, next 30 days 1.9%

Affects: Ios Xe

Remediation

A high-priority fix

Fix this in Ios Xe 12 hrs · Moderate

Typical engagement from $2,130

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2013-1164 and return a fixed quote and timeline.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

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.

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.

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.

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.

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.

Check your environment

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.

Scan for this in your stack

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

Practitioner notes

No notes yet

Official description

Technical summary

Affected products & versions

CVSS breakdown

Am I affected?

Remediation

References