{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68142", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.370Z", "datePublished": "2026-08-10T11:59:06.048Z", "dateUpdated": "2026-08-19T16:30:02.355Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:30:02.355Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ngeneve: require CAP_NET_ADMIN in the device netns for changelink\n\nA tunnel changelink() operates on at most two netns, dev_net(dev) and\nthe sticky underlay netns geneve->net. They differ once the device is\ncreated in or moved to a netns other than the one the request runs in.\nThe rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev),\nso a caller privileged there but not in geneve->net can rewrite a geneve\ndevice whose underlay lives in geneve->net.\n\ngeneve_changelink() applies the new configuration against geneve->net:\ngeneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair\nreopen the underlay sockets in that netns (geneve_sock_add() uses\ngeneve->net), so the same reasoning as the tunnel changelink series\napplies here.\n\nGate geneve_changelink() with rtnl_dev_link_net_capable(), at the top of\nthe op before any attribute is parsed, matching ipgre_changelink() and\nthe rest of the \"require CAP_NET_ADMIN in the device netns for\nchangelink\" series.\n\nFound by 0sec automated security-research tooling (https://0sec.ai)." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Exploitation requires issuing RTM_NEWLINK changelink over a local rtnetlink socket; geneve_changelink is only reachable from the rtnl configuration path, not from received GENEVE/UDP network packets.\nAC:L - Once a geneve device exists with geneve->net differing from dev_net(dev) (via IFLA_NET_NS_FD migration or IFLA_LINK_NETNSID newlink), a single deterministic netlink changelink bypasses the missing check with no race or memory-layout dependency.\nPR:L - The rtnl entry path requires CAP_NET_ADMIN in dev_net(dev), obtainable by an unprivileged local user inside a user+network namespace via unshare --user --map-root-user --net; no CAP_NET_ADMIN in the sticky underlay netns geneve->net is needed.\nUI:N - The attack is fully programmatic through netlink from the attacker's own process; no victim action such as mounting a filesystem, opening a file, or clicking is required.\nS:C - geneve_changelink applies geneve_link_config() and geneve_quiesce()/geneve_unquiesce() (reopening underlay sockets via geneve_sock_add() in geneve->net) while authorization is checked only against dev_net(dev), crossing into another tenant's or the host's network namespace.\nC:H - An attacker can set IFLA_GENEVE_REMOTE/REMOTE6 to redirect encapsulated overlay traffic to an attacker-controlled endpoint and read tunneled payloads from the victim underlay netns.\nI:H - Unauthorized changelink mutates live tunnel remote endpoint, TTL/TOS/DF/label, and MTU in geneve->net, enabling redirection and injection of overlay traffic without authorization in that namespace.\nA:H - geneve_quiesce() drops in-flight tunnel traffic and rewriting the remote endpoint or MTU breaks production GENEVE overlays (Kubernetes/OVN/cloud SDN), causing sustained loss of connectivity for dependent services." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/geneve.c" ], "versions": [ { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "a5522963c57f12df5f9db804ebfc472b58eef0ae", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "278c6a31ee27c931c722202c8c06cc3253923254", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "11a7d989d00160481a273eb4f7f05f64b5a6ffdf", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "2abdacc927c92fa6a9cc8341e8c9b88dcb561553", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "9de5518fc1fab583526a8f66b8e505c4864dc60a", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "f8c498585d2a08aa623748353c3e61467b7e9fd2", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "95f45e20f1b2cec13823f0f68060ab4b2261b2c1", "status": "affected", "versionType": "git" }, { "version": "5b861f6baa3a22a48d7a4ad0ce38a223d36c978a", "lessThan": "8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/geneve.c" ], "versions": [ { "version": "4.14", "status": "affected" }, { "version": "0", "lessThan": "4.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "4.14", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a5522963c57f12df5f9db804ebfc472b58eef0ae" }, { "url": "https://git.kernel.org/stable/c/278c6a31ee27c931c722202c8c06cc3253923254" }, { "url": "https://git.kernel.org/stable/c/11a7d989d00160481a273eb4f7f05f64b5a6ffdf" }, { "url": "https://git.kernel.org/stable/c/2abdacc927c92fa6a9cc8341e8c9b88dcb561553" }, { "url": "https://git.kernel.org/stable/c/9de5518fc1fab583526a8f66b8e505c4864dc60a" }, { "url": "https://git.kernel.org/stable/c/f8c498585d2a08aa623748353c3e61467b7e9fd2" }, { "url": "https://git.kernel.org/stable/c/95f45e20f1b2cec13823f0f68060ab4b2261b2c1" }, { "url": "https://git.kernel.org/stable/c/8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01" } ], "title": "geneve: require CAP_NET_ADMIN in the device netns for changelink", "x_generator": { "engine": "bippy-1.2.0" } } } }