FreeBSD : FreeBSD -- Resource exhaustion due to sessions stuck in LAST_ACK state (0c064c43-600a-11e6-a6c3-14dae9d210b8)

high Nessus Plugin ID 92889


The remote FreeBSD host is missing one or more security-related updates.


TCP connections transitioning to the LAST_ACK state can become permanently stuck due to mishandling of protocol state in certain situations, which in turn can lead to accumulated consumption and eventual exhaustion of system resources, such as mbufs and sockets.
Impact : An attacker who can repeatedly establish TCP connections to a victim system (for instance, a Web server) could create many TCP connections that are stuck in LAST_ACK state and cause resource exhaustion, resulting in a denial of service condition. This may also happen in normal operation where no intentional attack is conducted, but an attacker who can send specifically crafted packets can trigger this more reliably.


Update the affected packages.

See Also

Plugin Details

Severity: High

ID: 92889

File Name: freebsd_pkg_0c064c43600a11e6a6c314dae9d210b8.nasl

Version: 2.4

Type: local

Published: 8/12/2016

Updated: 1/4/2021

Configuration: Enable paranoid mode

Risk Information


Risk Factor: Low

Score: 3.4


Risk Factor: High

Base Score: 7.1

Vector: AV:N/AC:M/Au:N/C:N/I:N/A:C

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:FreeBSD, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info, Settings/ParanoidReport

Patch Publication Date: 8/11/2016

Vulnerability Publication Date: 7/21/2015

Reference Information

CVE: CVE-2015-5358

FreeBSD: SA-15:13.tcp