Description
The IPv6 UDP send path for unconnected sockets did not apply the jail policy of rewriting a loopback destination address to the jail's primary IPv6 address.
A process in a classic (non-VNET) jail can send UDP datagrams to services listening on the host's IPv6 loopback address, bypassing jail network isolation.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| FreeBSD | FreeBSD | 15.1-RELEASE – < p4, 15.0-RELEASE – < p14, 14.5-RELEASE – < p1, 14.4-RELEASE – < p10 | p4 |
Advisories 1
- WID-SEC-2026-3664 FreeBSD Project FreeBSD OS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 14, 2026
References
- https://security.freebsd.org/advisories/FreeBSD-SA-26:69.udp.asc vendor-advisory