Adaptive Security Appliance SoftwareOperating system · Cisco
CVE-2015-6327
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 · uneditedThe IKEv1 implementation in Cisco Adaptive Security Appliance (ASA) software 7.2 and 8.2 before 8.2(5.58), 8.3 and 8.4 before 8.4(7.29), 8.5 through 8.7 before 8.7(1.17), 9.0 before 9.0(4.37), 9.1 before 9.1(6.8), 9.2 before 9.2(4), and 9.3 before 9.3(3) allows remote attackers to cause a denial of service (device reload) via crafted ISAKMP UDP packets, aka Bug ID CSCus94026.
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 confidenceA vulnerability exists in the IKEv1 implementation of Cisco ASA software where crafted ISAKMP UDP packets can trigger a denial of service, causing the device to reload. The issue affects multiple version branches from 7.2 through 9.3 and is caused by insufficient validation of IKEv1 packets.
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
Adaptive Security Appliance SoftwareOperating system
= 7.2.1= 7.2.1.9= 7.2.1.13= 7.2.1.19= 7.2.1.24= 7.2.2= 7.2.2.6= 7.2.2.10= 7.2.2.14= 7.2.2.18= 7.2.2.19= 7.2.2.22CVSS 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 checksWork through these to decide whether this CVE applies to you.
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Check Cisco ASA software versionRun the command 'show version' in the ASA CLI to obtain the installed software versionAffected if The installed version matches or falls within the affected range: 7.2.x through 9.3.x branches as noted in the CVE summary
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Verify IKEv1 is enabledRun 'show crypto isakmp policy' or 'show run crypto isakmp' to display IKEv1 policy configurationAffected if Any IKEv1 policies are configured, indicating IKEv1 is enabled on the device
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Confirm active IKEv1 security associationsRun 'show crypto isakmp sa' to display active IKE Security AssociationsAffected if Any IKEv1 SAs are active, meaning the device is currently processing IKEv1 traffic
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Check if IKEv1 UDP ports are reachableReview border ACLs or interface configurations to determine if UDP port 500 (ISAKMP) is permitted inboundAffected if UDP port 500 is accessible from untrusted networks, allowing crafted packets to reach the IKEv1 implementation
The device is affected if it runs an ASA version in the 7.2.x through 9.3.x range AND has IKEv1 enabled or active, with UDP port 500 reachable from external interfaces.
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 dataApply the appropriate Cisco ASA software update (8.2(5.58), 8.4(7.29), 8.7(1.17), 9.0(4.37), 9.1(6.8), 9.2(4), or 9.3(3) or later) to address the vulnerability. Consider restricting IKEv1 traffic at network borders using ACLs as a compensating control if immediate patching is not feasible.
Fix this in Adaptive Security Appliance Software
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2015-6327 — 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-2015-6327 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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