CVE-2006-5873

CVE-2006-5873 is a high-severity vulnerability in L2tpns with a CVSS 2.0 base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

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.

Frequently asked questions

What is CVE-2006-5873?
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.
How severe is CVE-2006-5873?
CVE-2006-5873 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2006-5873 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-5873?
CVE-2006-5873 primarily affects L2tpns. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2006-5873?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2006-5873 published?
CVE-2006-5873 was published on 2006-12-12 and last updated on 2026-06-16.

References

Affected products (4)