{"id":"CVE-2026-52909","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_vti: set netns_immutable on the fallback device.\n\njohn1988 and Noam Rathaus reported that vti6_init_net() does not set the\nnetns_immutable flag on the per-netns fal…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_vti: set netns_immutable on the fallback device.\n\njohn1988 and Noam Rathaus reported that vti6_init_net() does not set the\nnetns_immutable flag on the per-netns fal…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","published":"2026-06-19","updated":"2026-07-04","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-52909","references":[{"url":"https://git.kernel.org/stable/c/12acc977838c943636fb01e2f3087d2e4cc3b7cc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/12c65e2c7fef507551bd7b52123598a761662c01","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7f28e3948c59481f8db9c9638e204258d26b4e41","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c5dbd669db5a426b3025512322e1bf2cdbe14305","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d289d5307762d1838aaece22c6b6fcad9e8865f9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dcdce3bc9f08026ff3739ee7339e1bef526fc5f3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ecf8904067dcba0dad86ece80874841e60317885","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f4b6b4af7ef0661ac153c6f7eb1030aa8482c1a3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.0012,"epssPercentile":0.02125,"ingestedAt":"2026-07-04T12:56:09.602Z","slug":"CVE-2026-52909","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nip6_vti: set netns_immutable on the fallback device.\n\njohn1988 and Noam Rathaus reported that vti6_init_net() does not set the\nnetns_immutable flag on the per-netns fallback tunnel device (ip6_vti0).\n\nOther similar tunnel drivers (like ip6_tunnel, sit, ip6_gre, and ip_tunnel)\ncorrectly set this flag during their fallback device initialization to\nprevent them from being moved to another network namespace.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}