{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-52909", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.366Z", "datePublished": "2026-06-19T14:43:33.214Z", "dateUpdated": "2026-08-05T12:31:32.616Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:31:32.616Z" }, "descriptions": [ { "lang": "en", "value": "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 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." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable operation is reached through local rtnetlink device movement, such as RTM_SETLINK with IFLA_NET_NS_FD, not by unauthenticated remote packets.\nAC:L - An attacker can deterministically create or use network namespaces and move ip6_vti0; no race, special timing, or external condition is required.\nPR:L - The path requires CAP_NET_ADMIN in the relevant network namespace, but that is reachable from an unprivileged user via user namespaces on common deployments.\nUI:N - No victim action is required once the attacker can issue the local netlink operation.\nS:U - The impact remains within the kernel/network-namespace security authority and does not cross a VM, IOMMU, or separate hardware-enforced boundary.\nC:H - Moving the singleton fallback device leaves vti6 per-netns tunnel state pointing at a device in another namespace, which can expose VTI/XFRM tunnel traffic or namespace-scoped network state through an attacker-controlled device.\nI:H - The same cross-namespace device/state mismatch can let the attacker redirect or manipulate VTI6 tunnel delivery and per-netns tunnel semantics, so high integrity impact is defensible.\nA:H - The fallback device is assumed to be one immutable device per netns; violating that invariant can unregister or corrupt tunnel state and related vti6 namespace-migration bugs have produced cleanup-time UAF/BUG conditions." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/ip6_vti.c" ], "versions": [ { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "12acc977838c943636fb01e2f3087d2e4cc3b7cc", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "7f28e3948c59481f8db9c9638e204258d26b4e41", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "12c65e2c7fef507551bd7b52123598a761662c01", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "f4b6b4af7ef0661ac153c6f7eb1030aa8482c1a3", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "c5dbd669db5a426b3025512322e1bf2cdbe14305", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "ecf8904067dcba0dad86ece80874841e60317885", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "dcdce3bc9f08026ff3739ee7339e1bef526fc5f3", "status": "affected", "versionType": "git" }, { "version": "61220ab349485d911083d0b7990ccd3db6c63297", "lessThan": "d289d5307762d1838aaece22c6b6fcad9e8865f9", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/ip6_vti.c" ], "versions": [ { "version": "3.15", "status": "affected" }, { "version": "0", "lessThan": "3.15", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.260", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.211", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.177", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.144", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.95", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.36", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.13", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "5.10.260" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "5.15.211" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.1.177" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.6.144" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.12.95" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "6.18.36" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "7.0.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.15", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/12acc977838c943636fb01e2f3087d2e4cc3b7cc" }, { "url": "https://git.kernel.org/stable/c/7f28e3948c59481f8db9c9638e204258d26b4e41" }, { "url": "https://git.kernel.org/stable/c/12c65e2c7fef507551bd7b52123598a761662c01" }, { "url": "https://git.kernel.org/stable/c/f4b6b4af7ef0661ac153c6f7eb1030aa8482c1a3" }, { "url": "https://git.kernel.org/stable/c/c5dbd669db5a426b3025512322e1bf2cdbe14305" }, { "url": "https://git.kernel.org/stable/c/ecf8904067dcba0dad86ece80874841e60317885" }, { "url": "https://git.kernel.org/stable/c/dcdce3bc9f08026ff3739ee7339e1bef526fc5f3" }, { "url": "https://git.kernel.org/stable/c/d289d5307762d1838aaece22c6b6fcad9e8865f9" } ], "title": "ip6_vti: set netns_immutable on the fallback device.", "x_generator": { "engine": "bippy-1.2.0" } } } }