CVE-2026-78135

libcharon in strongSwan 5.9.7 through 6.0.7 mishandles behavioral workflow in the IKEv2 state machine. Because CREATE_CHILD_SA requests are mishandled, there can be an authentication bypass.

CVSS v3 5.6 MEDIUM

5.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/strongswan/strongswan/releases/tag/6.1.0	Release Notes Vendor Advisory
https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78135).html	Vendor Advisory Mitigation

Configurations

Configuration 1 (hide)

cpe:2.3:a:strongswan:strongswan:*:*:*:*:*:*:*:*

History

16 Sep 2026, 19:37

Type	Values Removed	Values Added
First Time		Strongswan Strongswan strongswan
CPE		cpe:2.3:a:strongswan:strongswan::::::::
References	~~() https://github.com/strongswan/strongswan/releases/tag/6.1.0 -~~	() https://github.com/strongswan/strongswan/releases/tag/6.1.0 - Release Notes, Vendor Advisory
References	~~() https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78135).html -~~	() https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78135).html - Vendor Advisory, Mitigation

Information

Published : 2026-09-11 03:16

Updated : 2026-09-16 19:37

NVD link : CVE-2026-78135

Mitre link : CVE-2026-78135

CVE.ORG link : CVE-2026-78135

JSON object : View

Products Affected

strongswan

strongswan

CWE

CWE-841

Improper Enforcement of Behavioral Workflow

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