UnityApplication · Cisco
CVE-2008-4543
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 · uneditedCisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to cause a denial of service (session exhaustion) via a large number of connections.
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 Unity versions 4.x, 5.x, and 7.x contain a denial of service vulnerability when anonymous authentication is enabled. Attackers can exhaust available sessions by opening a large number of connections, preventing legitimate users from accessing the system.
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
UnityApplication
<= 4.2\(1\)<= 5.0\(1\)<= 7.0\(2\)= 4.0= 4.0\(1\)= 4.0\(2\)= 4.0\(3\)= 4.0\(4\)= 4.0\(5\)= 4.1\(1\)= 5.0= 7.0CVSS 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
- M
- Authentication
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- Complete
AV:N/AC:M/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 checksWork through these to decide whether this CVE applies to you.
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Identify Cisco Unity versionAccess the Cisco Unity administration interface or server system information to determine the installed Unity version number (typically found in Unity About or System Diagnostics)Affected if The installed version matches any of: 4.0, 4.0(1), 4.0(2), 4.0(3), 4.0(4), 4.0(5), 4.1(1), 4.2(1) and below; 5.0, 5.0(1) and below; or 7.0, 7.0(2) and below
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Verify anonymous authentication statusLocate the authentication settings within the Cisco Unity administration console (typically under Security, Directory, or Messaging settings) and determine whether anonymous authentication is enabledAffected if Anonymous authentication is set to Enabled or Allowed for the Unity system
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Confirm Unity service accessibilityVerify that the Cisco Unity server is accepting external connections on its messaging ports (commonly port 25 for SMTP or 5060 for SIP, depending on configuration)Affected if The Unity server is reachable and accepting connections, allowing potential attackers to initiate the session exhaustion attack
The environment is affected if Cisco Unity is running any version up to 4.2(1), 5.0(1), or 7.0(2) AND anonymous authentication is currently enabled on the system.
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 dataUpgrade Cisco Unity to version 4.2(1)ES161, 5.0(1)ES53, 7.0(2)ES8 or later. If immediate upgrade is not feasible, consider disabling anonymous authentication and enforcing authenticated access until the upgrade can be performed.
Fix this in Unity
Scoped from the published advisory
- Consultation3.0 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 $5,280.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2008-4543 — 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-2008-4543 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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