---
id: CVE-2026-94453
title: >-
  Libreswan's pluto daemon has a use-after-free vulnerability when a client
  connecting using IKE over TCP closes the connection and another packet
  (retransmit or malicious) is received for the same tuple
summary: >-
  Libreswan's pluto daemon has a use-after-free vulnerability when a client
  connecting using IKE over TCP closes the connection and another packet
  (retransmit or malicious) is received for the same tuple. IKE state is
  retained in memory af…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-416
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T22:19:30.253'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-94453'
references:
  - url: 'https://libreswan.org/security/CVE-2026-94453/'
    label: d42dc95b-23f1-4e06-9076-20753a0fb0df
  - url: 'https://libreswan.org/security/CVE-2026-94453/CVE-2026-94453.txt'
    label: d42dc95b-23f1-4e06-9076-20753a0fb0df
tags:
  - nvd
ingestedAt: '2026-10-13T23:03:54.751Z'
---

## Overview

Libreswan's pluto daemon has a use-after-free vulnerability when a client connecting using IKE over TCP closes the connection and another packet (retransmit or malicious) is received for the same tuple. IKE state is retained in memory after the client closes the connection, storing a pointer to iface_endpoint inside ike_sa.sa->st_iface_endpoint. Once this invalid pointer is used, the daemon crashes and restarts. This vulnerability can be triggered before the remote peer has authenticated itself. Continued exploitation can lead to a denial of service. Remote code execution could be possible. The IKE over TCP option is not enabled by default; only configurations that contain listen-tcp=yes are affected.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.