Unified Ip Phone 6911 FirmwareOperating system · Cisco
CVE-2022-20817
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 · uneditedA vulnerability in Cisco Unified IP Phones could allow an unauthenticated, remote attacker to impersonate another user's phone if the Cisco Unified Communications Manager (CUCM) is in secure mode. This vulnerability is due to improper key generation during the manufacturing process that could result in duplicated manufactured keys installed on multiple devices. An attacker could exploit this vulnerability by performing a machine-in-the-middle attack on the secure communication between the phone and the CUCM. A successful exploit could allow the attacker to impersonate another user's phone. This vulnerability cannot be addressed with software updates. There is a workaround that addresses this vulnerability.
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 confidenceCisco Unified IP Phones contain duplicated manufacturing keys due to improper key generation during production. When CUCM operates in secure mode, an attacker performing a machine-in-the-middle attack can use these duplicated keys to decrypt and impersonate another user's phone, gaining unauthorized access to their communications and identity.
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
Unified Ip Phone 6911 FirmwareOperating system
all versions
Unified Ip Phone 6921 FirmwareOperating system
all versions
Unified Ip Phone 6941 FirmwareOperating system
all versions
Unified Ip Phone 6945 FirmwareOperating system
all versions
Unified Ip Phone 6961 FirmwareOperating system
all versions
Unified Ip Phone 8941 FirmwareOperating system
all versions
Unified Ip Phone 8945 FirmwareOperating system
all versions
Unified Ip Phone 8961 FirmwareOperating system
all versionsCVSS 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
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 checksWork through these to decide whether this CVE applies to you.
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Identify affected phone models in your environmentInventory your Cisco IP phones and check if any are models 6911, 6921, 6941, 6945, 6961, 8941, 8945, or 8961. Use CUCM device inventory reports or network discovery to list installed phone types.Affected if Any of these eight model numbers are present in your deployment, regardless of firmware version, because all firmware versions for these models are affected.
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Determine CUCM security modeCheck the Cisco Unified Communications Manager security mode configuration. In CUCM Administration, go to System > Security > Security Profile or review the cluster security settings to confirm whether secure mode (TLS authentication) is enabled.Affected if CUCM is operating in secure mode. The vulnerability only applies when secure mode is enabled; if CUCM uses non-secure mode, the duplicated keys cannot be exploited for MITM attacks.
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Verify phone firmware versionQuery the phone firmware version via CUCM reports (Device > Firmware Information) or directly from the phone web interface or SIP headers. Compare against all available firmware releases for your phone models.Affected if The phones are running any firmware version (all versions are affected). There is no fixed version since this is a manufacturing key defect, not a software vulnerability.
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Assess network proximity riskEvaluate whether an attacker could position themselves between phones and CUCM. Check for shared network segments, lack of 802.1X port security, or unmanaged switch ports that could enable a machine-in-the-middle position.Affected if Phones are on network segments where an attacker could intercept traffic between the phone and CUCM. The attack requires the attacker to have MITM capability.
You are affected if you have any of the eight phone models (6911, 6921, 6941, 6945, 6961, 8941, 8945, 8961) deployed AND your CUCM is running in secure mode, because the duplicated manufacturing keys exist in all firmware versions of these devices.
Generated from the published advisory. Verify against your own configuration.
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 dataSince this is a hardware/manufacturing defect not fixable via software updates, organizations should implement the documented workaround (typically involving certificate management or secure mode configuration) and consider hardware replacement with properly provisioned devices.
Fix this in Unified Ip Phone 6911 Firmware
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-20817 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-20817 in production — separate from our analysis above.
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
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- Version or environment caveats, and links to real fixes
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