{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68299", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.380Z", "datePublished": "2026-08-10T12:02:33.213Z", "dateUpdated": "2026-08-19T16:32:48.545Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:32:48.545Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets\n\nvmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the\nouter header, but for a Geneve-encapsulated packet the device can set\nthem based on the inner header instead, signalled by the\nVMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the\nfunction never skips the outer encapsulation, this mismatch triggers:\n\n- BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer\n protocol is UDP (Geneve), not TCP.\n- BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner\n IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa).\n\nCheck VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the\nfunction cannot locate the inner header it would need to parse. Also\nconvert the remaining BUG_ON()s in this function to return 0\ndefensively." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is triggered purely by a received Geneve-encapsulated packet processed in the vmxnet3 RX completion path (vmxnet3_rq_rx_complete -> vmxnet3_get_hdr_len); any remote host that can deliver such a frame to a VMware guest's vmxnet3 interface reaches the code, with no local access required.\nAC:L - The attacker only needs to send Geneve-encapsulated TCP traffic larger than the MTU to the target; the device then sets rcd.v4/v6/tcp from the inner header and the outer UDP protocol (or an outer/inner IP version mismatch) deterministically hits the BUG_ON, with no race or memory-layout dependency.\nPR:N - Packet reception and header-length estimation occur in the driver's NAPI RX path before any socket, credential, or authentication check, so an entirely unauthenticated remote sender triggers it.\nUI:N - The panic happens during normal NAPI RX processing of an incoming packet; no action by any local user or administrator is needed.\nS:U - The BUG_ON crashes the kernel that owns the vmxnet3 interface, and impact stays entirely within that kernel's security authority with no crossing into the hypervisor or another domain.\nC:N - The header parsing is bounded by the explicit skb_headlen()/maplen checks, so no out-of-bounds read occurs and no kernel memory contents are disclosed to the attacker before the BUG_ON aborts.\nI:N - No out-of-bounds or attacker-controlled write occurs; the mismatch is caught by the BUG_ON assertion, which halts execution rather than corrupting kernel memory or control flow.\nA:H - Hitting BUG_ON() in softirq/NAPI context oopses and panics the kernel, taking down the entire guest; a remote attacker can repeat it with a single crafted Geneve packet stream for a persistent denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/vmxnet3/vmxnet3_drv.c" ], "versions": [ { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "fbab6b73cc086e32698c86e43d1b16bf17d24c36", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "28e382646417c7e2be9c9a7079eddf627ff52b90", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "667b6e52048eaf4dbcf1707ed87ffd44abb9cb38", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "4fdb0f162ccdbe9626863b10003855703253fa29", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "b28596baf87e25a078789f1c05817c8a3bf71257", "status": "affected", "versionType": "git" }, { "version": "45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc", "lessThan": "34a71f5361fc3adb5b7138da78750b0d535a8252", "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/vmxnet3/vmxnet3_drv.c" ], "versions": [ { "version": "4.2", "status": "affected" }, { "version": "0", "lessThan": "4.2", "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": "4.2", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0" }, { "url": "https://git.kernel.org/stable/c/fbab6b73cc086e32698c86e43d1b16bf17d24c36" }, { "url": "https://git.kernel.org/stable/c/28e382646417c7e2be9c9a7079eddf627ff52b90" }, { "url": "https://git.kernel.org/stable/c/667b6e52048eaf4dbcf1707ed87ffd44abb9cb38" }, { "url": "https://git.kernel.org/stable/c/28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8" }, { "url": "https://git.kernel.org/stable/c/4fdb0f162ccdbe9626863b10003855703253fa29" }, { "url": "https://git.kernel.org/stable/c/b28596baf87e25a078789f1c05817c8a3bf71257" }, { "url": "https://git.kernel.org/stable/c/34a71f5361fc3adb5b7138da78750b0d535a8252" } ], "title": "vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets", "x_generator": { "engine": "bippy-1.2.0" } } } }