Libreswan Project up to 5.3.2/5.4/5.4.0 IKE State st_iface_endpoint use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Libreswan Project Libreswan up to 5.3.2/5.4/5.4.0. Affected by this vulnerability is an unknown functionality of the component IKE State. The manipulation of the argument st_iface_endpoint results in use after free. This vulnerability is known as CVE-2026-94453. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Libreswan Project Libreswan up to 5.3.2/5.4/5.4.0. Affected is an unknown functionality of the component IKE State. The manipulation of the argument st_iface_endpoint with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on availability. CVE summarizes:

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.

The advisory is shared for download at libreswan.org. This vulnerability is traded as CVE-2026-94453 since 09/21/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

Upgrading to version 5.3.3 or 5.4.1 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (libreswan): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Libreswan 5.3.3/5.4.1

Timelineinfo

09/21/2026 CVE reserved
10/13/2026 +22 days VulDB entry created
10/14/2026 +0 days Advisory disclosed
10/14/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: libreswan.org
Status: Confirmed

CVE: CVE-2026-94453 (🔒)
GCVE (CVE): GCVE-0-2026-94453
GCVE (VulDB): GCVE-100-418440

Entryinfo

Created: 10/14/2026 00:10
Changes: 10/14/2026 00:10 (65)
Complete: 🔍
Cache ID: 216::103

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