dbcve.org
iOSOperating system · Cisco

CVE-2011-2072

HIGH · 7.8 CVSS v2.0 Published 2011-10-03
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 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
Memory leak in Cisco IOS 12.4, 15.0, and 15.1, Cisco IOS XE 2.5.x through 3.2.x, and Cisco Unified Communications Manager (CUCM) 6.x and 7.x before 7.1(5b)su4, 8.x before 8.5(1)su2, and 8.6 before 8.6(1) allows remote attackers to cause a denial of service (memory consumption and device reload or process failure) via a malformed SIP message, aka Bug IDs CSCtl86047 and CSCto88686.

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

Memory leak vulnerability in Cisco IOS, IOS XE, and CUCM allows remote attackers to send malformed SIP messages causing memory exhaustion. This leads to denial of service through device reload or process failure. The vulnerability affects specific versions of SIP implementation in Cisco's voice and networking infrastructure products.

MitigationApply Cisco security updates: upgrade to CUCM 7.1(5b)su4, 8.5(1)su2, or 8.6(1) and later; apply relevant IOS/IOS XE patches for Bug IDs CSCtl86047 and CSCto88686. Consider SIP message filtering at network edge as interim control.

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:= 12.4= 15.0= 15.1
Ios XeOperating system
Affected:= 2.5.0= 2.5.1= 2.5.2= 2.6.0= 2.6.1= 2.6.2= 3.1.0s= 3.1.1s= 3.1.2s= 3.1.3s= 3.1.4s= 3.2.0s
Unified Communications ManagerApplication
Affected:= 6.0= 6.1\(1\)= 6.1\(1a\)= 6.1\(1b\)= 6.1\(2\)= 6.1\(2\)su1= 6.1\(2\)su1a= 6.1\(3\)= 6.1\(3a\)= 6.1\(3b\)= 6.1\(3b\)su1= 6.1\(4\)

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
Authentication
None
Confidentiality
None
Integrity
None
Availability
Complete

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

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 Cisco product running
    Access the device CLI or admin interface and run 'show version' on iOS/IOS XE devices, or check the About page in the CUCM Administration interface
    Affected if The device is running Cisco iOS, IOS XE, or Unified Communications Manager (CUCM)
  2. Check the iOS version
    Run 'show version' and locate the software version number in the output
    Affected if The version matches 12.4, 15.0, or 15.1 (exact match)
  3. Check the IOS XE version
    Run 'show version' and locate the software version number in the output
    Affected if The version matches any of: 2.5.0, 2.5.1, 2.5.2, 2.6.0, 2.6.1, 2.6.2, 3.1.0s, 3.1.1s, 3.1.2s, 3.1.3s, 3.1.4s, 3.2.0s (exact match)
  4. Check the CUCM version
    Log into CUCM Administration, navigate to About > Licensing, or run 'utils system version' from the CLI
    Affected if The version matches any of: 6.0, 6.1(1), 6.1(1a), 6.1(1b), 6.1(2), 6.1(2)su1, 6.1(2)su1a, 6.1(3), 6.1(3a), 6.1(3b), 6.1(3b)su1, 6.1(4) (exact match)
  5. Verify SIP is enabled on the device
    On iOS/IOS XE: run 'show sip' or 'show voip sip'; on CUCM: check SIP trunk configuration in CUCM Administration under Device > Trunk
    Affected if SIP protocol is configured or enabled as a VoIP signaling method

The device is affected if it runs a matching version of iOS, IOS XE, or CUCM AND has SIP protocol enabled or configured.

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: upgrade to CUCM 7.1(5b)su4, 8.5(1)su2, or 8.6(1) and later; apply relevant IOS/IOS XE patches for Bug IDs CSCtl86047 and CSCto88686. Consider SIP message filtering at network edge as interim control.

Fix this in iOS Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA4.0 h
40.0 hours of engineering $7,000
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $11,200.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2011-2072 — 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-2011-2072 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