CVE-2006-5873 Denial of service in n/a

What is CVE-2006-5873?

CVE-2006-5873 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 12 Dec 2006. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Buffer overflow in the cluster_process_heartbeat function in cluster.c in layer 2 tunneling protocol network server (l2tpns) before 2.1.21 allows remote attackers to cause a denial of service via a large heartbeat packet.

Which versions are affected by CVE-2006-5873?

It affects 2 products.

Products include Debian Debian Linux, L2tpns L2tpns.

How do I fix CVE-2006-5873?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2006-5873 being exploited?

There is no known exploitation of CVE-2006-5873 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

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• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as CVE-2006-6362, DEBIAN-CVE-2006-5873, DSA-1230-1, GHSA-548f-88j9-xqq6.