CVE-2026-94453 (GCVE-0-2026-94453)

Vulnerability from cvelistv5 – Published: 2026-10-13 21:27 – Updated: 2026-10-13 21:27
VLAI
Title
IKEv2 Use-After-Free bug when using IKE-over-TCP
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 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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
libreswan CNA under the mitre root
CNA scorecard – unranked: 8 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
The Libreswan Project libreswan Affected: 4.0 , ≤ 5.3.2 (semver)
Affected: 5.4 , ≤ 5.4 (semver)
Unaffected: 5.3.3 (semver)
Unaffected: 5.4.1 (semver)
guessed Create a notification for this product.
Credits
Vlad Miu
Show details on NVD website
To clipboard 

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        }
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          "lang": "en",
          "value": "Upgrade to libreswan 5.3.3 or 5.4.1 or later. Patches are available at https://libreswan.org/security/CVE-2026-94453/"
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          "time": "2026-10-05T00:00:00.000Z",
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      "title": "libreswan: IKEv2 Use-After-Free bug when using IKE-over-TCP",
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}



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