CVE-2026-94453
Reported by libreswan · Published October 13, 2026
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.
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| The Libreswan Project | libreswan | 4.0, 5.4, 5.3.3 |
| The Libreswan Project | libreswan | 4.0, 5.4, 5.3.3 |
| amazon:2023 | libreswan | 0 |
| alpine | libreswan | 0 |
Timeline
- Oct 13, 2026 CVE Published
- Oct 14, 2026 EPSS Score
- Oct 16, 2026 EPSS Score
- Oct 16, 2026 CVE Updated
- Oct 20, 2026 EPSS Score
- Oct 21, 2026 EPSS Score
- Oct 24, 2026 EPSS Score
- Oct 25, 2026 EPSS Score
- Oct 27, 2026 Distribution Patch
- Oct 27, 2026 Security Advisory
- Oct 29, 2026 EPSS Score
- Nov 2, 2026 Distribution Patch
References
- Libreswan Security Advisory CVE-2026-94453 vendor-advisory
- Libreswan CVE-2026-94453 Patches patch