CVE-2000-1027

Cisco Secure PIX Firewall 5.2(2) allows remote attackers to determine the real IP address of a target FTP server by flooding the server with PASV requests, which includes the real IP address in the response when passive mode is established.

What this means for your business

It affects Cisco Pix Firewall Software. It matters if your company, or a supplier that handles your data, runs it.
Code showing how to exploit it has been published, but real attacks have not been confirmed.
An attacker can use it remotely, over a network.
FIRST's prediction model gives it a 4% chance of attack attempts being seen in the next 30 days, ranking above 88% of all known flaws.

What to do

1Check whether your company or your suppliers run Cisco Pix Firewall Software, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

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Scoring

CVSS: 5.0 (v2.0)
Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N
Assigned by: cve@mitre.org

Dates

Published: 2000-12-11
Last modified: 2026-09-23
Sources: NVD

Affected products

Cisco Pix Firewall Software5.2

As listed in the NVD configuration data. Not a statement about your estate.