IKEv2 Use-After-Free bug when using IKE-over-TCP (The Libreswan Project libreswan)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.45 % · percentile 39 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- libreswan
- NVD status
- Awaiting Analysis
Description
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.
Weaknesses (CWE)
- CWE-416 — Use After Free
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | libreswan |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · d42dc95b-23f1-4e06-9076-20753a0fb0df (Secondary) |
European references
- ENISA EUVD · EUVD-2026-100744
- GCVE · GCVE-0-2026-94453
Affected products
| Product | Versions |
|---|---|
| The Libreswan Project · libreswan | affected 4.0 ≤ 5.3.2 ; affected 5.4 ≤ 5.4 ; unaffected 5.3.3 ; unaffected 5.4.1 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |