ip6_vti: set netns_immutable on the fallback device.

Summary

In the Linux kernel, the following vulnerability has been resolved: ip6_vti: set netns_immutable on the fallback device. john1988 and Noam Rathaus reported that vti6_init_net() does not set the netns_immutable flag on the per-netns fallback tunnel device (ip6_vti0). Other similar tunnel drivers (like ip6_tunnel, sit, ip6_gre, and ip_tunnel) correctly set this flag during their fallback device initialization to prevent them from being moved to another network namespace.

Timeline

1. Jun 19, 2026, 2:43 PM UTCCVE published
2. Oct 16, 2026, 3:22 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 19, 2026, 7:36 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in 12acc977838c943636fb01e2f3087d2e4cc3b7cc; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in 7f28e3948c59481f8db9c9638e204258d26b4e41; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in 12c65e2c7fef507551bd7b52123598a761662c01; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in f4b6b4af7ef0661ac153c6f7eb1030aa8482c1a3; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in c5dbd669db5a426b3025512322e1bf2cdbe14305; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in ecf8904067dcba0dad86ece80874841e60317885; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in dcdce3bc9f08026ff3739ee7339e1bef526fc5f3; From 61220ab349485d911083d0b7990ccd3db6c63297 · fixed in d289d5307762d1838aaece22c6b6fcad9e8865f9

• Linux Linux

  3.15

• KernelLinux

  From 3.15.0 · fixed in 5.10.260; From 5.11.0 · fixed in 5.15.211; From 5.16.0 · fixed in 6.1.177; From 6.2.0 · fixed in 6.6.144; From 6.7.0 · fixed in 6.12.95; From 6.13.0 · fixed in 6.18.36; From 6.19.0 · fixed in 7.0.13

References 8