{"id":"CVE-2026-31502","state":"PUBLISHED","title":"team: fix header_ops type confusion with non-Ethernet ports","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nteam: fix header_ops type confusion with non-Ethernet ports\n\nSimilar to commit 950803f72547 (\"bonding: fix type confusion in\nbond_setup_by_slave()\") team has the same class of header_ops type\nconfusion.\n\nFor non-Ethernet ports, team_setup_by_port() copies port_dev->header_ops\ndirectly. When the team device later calls dev_hard_header() or\ndev_parse_header(), these callbacks can run with the team net_device\ninstead of the real lower device, so netdev_priv(dev) is interpreted as\nthe wrong private type and can crash.\n\nThe syzbot report shows a crash in bond_header_create(), but the root\ncause is in team: the topology is gre -> bond -> team, and team calls\nthe inherited header_ops with its own net_device instead of the lower\ndevice, so bond_header_create() receives a team device and interprets\nnetdev_priv() as bonding private data, causing a type confusion crash.\n\nFix this by introducing team header_ops wrappers for create/parse,\nselecting a team port under RCU, and calling the lower device callbacks\nwith port->dev, so each callback always sees the correct net_device\ncontext.\n\nAlso pass the selected lower device to the lower parse callback, so\nrecursion is bounded in stacked non-Ethernet topologies and parse\ncallbacks always run with the correct device context.","publishedAt":"2026-04-22T13:54:22.481Z","updatedAt":"2026-10-30T12:24:17.203Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"c6e255b0ce30cdea37e34d6d87e2212eb8c7f7a4","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"6d3161fa3eee64d46b766fb0db33ec7f300ef52d","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"20491d384d973a63fbdaf7a71e38d69b0659ea55","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"425000dbf17373a4ab8be9428f5dc055ef870a56","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/team/team_core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.7","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.80","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.21","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.11","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/team/team_core.c"]}],"references":["https://git.kernel.org/stable/c/c6e255b0ce30cdea37e34d6d87e2212eb8c7f7a4","https://git.kernel.org/stable/c/420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53","https://git.kernel.org/stable/c/6d3161fa3eee64d46b766fb0db33ec7f300ef52d","https://git.kernel.org/stable/c/0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0","https://git.kernel.org/stable/c/20491d384d973a63fbdaf7a71e38d69b0659ea55","https://git.kernel.org/stable/c/425000dbf17373a4ab8be9428f5dc055ef870a56"],"weaknesses":["CWE-843"],"ingestedAt":"2026-10-30T12:42:04.495Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/31xxx/CVE-2026-31502.json","commit":"db8103c5921aac81d5d90efcf3745980dafabf49","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31502","state":"PUBLISHED","datePublished":"2026-04-22T13:54:22.481Z","dateUpdated":"2026-10-30T12:24:17.203Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-03-09T15:48:24.104Z"},"containers":{"cna":{"title":"team: fix header_ops type confusion with non-Ethernet ports","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nteam: fix header_ops type confusion with non-Ethernet ports\n\nSimilar to commit 950803f72547 (\"bonding: fix type confusion in\nbond_setup_by_slave()\") team has the same class of header_ops type\nconfusion.\n\nFor non-Ethernet ports, team_setup_by_port() copies port_dev->header_ops\ndirectly. When the team device later calls dev_hard_header() or\ndev_parse_header(), these callbacks can run with the team net_device\ninstead of the real lower device, so netdev_priv(dev) is interpreted as\nthe wrong private type and can crash.\n\nThe syzbot report shows a crash in bond_header_create(), but the root\ncause is in team: the topology is gre -> bond -> team, and team calls\nthe inherited header_ops with its own net_device instead of the lower\ndevice, so bond_header_create() receives a team device and interprets\nnetdev_priv() as bonding private data, causing a type confusion crash.\n\nFix this by introducing team header_ops wrappers for create/parse,\nselecting a team port under RCU, and calling the lower device callbacks\nwith port->dev, so each callback always sees the correct net_device\ncontext.\n\nAlso pass the selected lower device to the lower parse callback, so\nrecursion is bounded in stacked non-Ethernet topologies and parse\ncallbacks always run with the correct device context."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"c6e255b0ce30cdea37e34d6d87e2212eb8c7f7a4","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"6d3161fa3eee64d46b766fb0db33ec7f300ef52d","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"20491d384d973a63fbdaf7a71e38d69b0659ea55","versionType":"git"},{"version":"1d76efe1577b4323609b1bcbfafa8b731eda071a","status":"affected","lessThan":"425000dbf17373a4ab8be9428f5dc055ef870a56","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/team/team_core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.7","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.80","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.21","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.11","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/team/team_core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/c6e255b0ce30cdea37e34d6d87e2212eb8c7f7a4"},{"url":"https://git.kernel.org/stable/c/420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53"},{"url":"https://git.kernel.org/stable/c/6d3161fa3eee64d46b766fb0db33ec7f300ef52d"},{"url":"https://git.kernel.org/stable/c/0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0"},{"url":"https://git.kernel.org/stable/c/20491d384d973a63fbdaf7a71e38d69b0659ea55"},{"url":"https://git.kernel.org/stable/c/425000dbf17373a4ab8be9428f5dc055ef870a56"}],"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 - An attacker reaches the vulnerable team header_ops path by locally creating/enslaving network devices through rtnetlink and then triggering dev_hard_header()/dev_parse_header() via local packet/socket or network-stack activity on the malformed team device. The required setup is a local kernel networking configuration path rather than an unauthenticated packet-processing path.\nAC:L - The vulnerable topology, such as GRE -> bond -> team, is fully attacker-controlled once the required namespace capabilities are available, and triggering the bad callback is deterministic. There is no race or external timing condition required.\nPR:L - Creating team/bond/GRE devices and enslaving them requires CAP_NET_ADMIN, and packet sockets require CAP_NET_RAW, but both are available to an unprivileged user inside a user and network namespace on systems permitting unprivileged user namespaces. This is therefore low privileges, not real init-namespace root.\nUI:N - No victim interaction is required after the attacker has local access and namespace capabilities. The attacker can configure the devices and trigger the callback directly.\nS:U - The impact is within the same kernel security authority. This is a kernel crash/type-confusion or privilege-impact issue, not a VM escape or cross-scope boundary violation.\nC:H - The bug is a header_ops type confusion where callbacks interpret team private data as another subsystem's private structure, causing attacker-influenced kernel pointer dereferences and potential kernel memory exposure. Following the higher-severity rule for type confusion, confidentiality impact is high.\nI:H - Type confusion in kernel callback dispatch can lead to misinterpreted object pointers and potentially control-flow or write-primitive exploitation beyond the observed crash. Kernel type confusion is scored as high integrity impact.\nA:H - The reported and expected failure mode is a kernel oops/BUG/crash when the inherited callback uses the wrong net_device private layout. This gives high availability impact."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:24:17.203Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.12.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.18.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.19.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-31502","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:10:14.938095Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-843","lang":"en","type":"CWE","description":"CWE-843 Access of Resource Using Incompatible Type ('Type Confusion')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:45:53.793Z"}}]}}}