CVE-2000-0916

FreeBSD 4.1.1 and earlier, and possibly other BSD-based OSes, uses an insufficient random number generator to generate initial TCP sequence numbers (ISN), which allows remote attackers to spoof TCP connections.

What this means for your business

It affects Freebsd. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it remotely, over a network.

What to do

1Check whether your company or your suppliers run Freebsd, 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: 7.5 (v2.0)
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Assigned by: cve@mitre.org

Dates

Published: 2000-12-19
Last modified: 2026-09-23
Sources: NVD

Affected products

Freebsd Freebsd2.0, 3.0, 4.0, 4.1, 4.1.1

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