Pix FirewallApplication · Cisco
CVE-1999-1582
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 · uneditedBy design, the "established" command on the Cisco PIX firewall allows connections from one host to arbitrary ports of a target host if an alternative conduit has already been allowed, which can cause administrators to configure less restrictive access controls than intended if they do not understand this functionality.
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 confidenceThe Cisco PIX firewall's 'established' command, designed to allow return traffic for stateful inspection, has a design flaw where it can permit connections from one host to arbitrary ports on a target host if any alternative conduit has already been allowed. This can lead to administrators unintentionally creating less restrictive access controls when they rely on the established command without fully understanding its behavior.
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
Pix FirewallApplication
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
- Low
- Authentication
- None
- Confidentiality
- Partial
- Integrity
- Partial
- Availability
- Partial
AV:N/AC:L/Au:N/C:P/I:P/A:P
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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Confirm Cisco PIX firewall is in useIdentify the firewall device model and verify it is a Cisco PIX device. Check device inventory or issue 'show version' command to confirm PIX model and software version.Affected if The environment uses a Cisco PIX firewall device.
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Locate the 'established' command configurationReview the PIX running configuration and look for 'established' statements. Use 'show running-config' or inspect the configuration file for any 'established' keyword.Affected if The 'established' command is configured on the PIX firewall.
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Identify conduits that allow any-to-any accessExamine PIX conduit statements in the configuration. Look for conduits that permit traffic from one host to a target host without specific port restrictions, particularly conduits using 'any' as source or destination.Affected if A conduit exists that allows traffic from an external host to the internal host, creating an alternative path that the established command could leverage.
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Check ACL and conduit interactionReview the relationship between the established command and any conduits. Determine if the established command references hosts or networks that also have other less restrictive conduits configured.Affected if The established command is used in combination with conduits that provide broader access than intended, allowing return traffic from arbitrary ports.
A user is affected if their Cisco PIX firewall has the 'established' command configured alongside any conduit statements that provide alternative access paths to internal hosts.
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 dataReview and restrict all PIX firewall conduit and ACL configurations to ensure they are explicitly defined for specific source/destination/port combinations rather than relying on the established command for broad access. Consider migrating from legacy PIX to modern firewall solutions if still in use.
Fix this in Pix Firewall
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 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 $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-1999-1582 — 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-1999-1582 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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