{"id":"CVE-2026-80584","state":"PUBLISHED","title":"s390/qeth: validate user buffer length in SNMP and ARP query ioctls","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/qeth: validate user buffer length in SNMP and ARP query ioctls\n\nqeth_snmp_command() and qeth_l3_arp_query() allocate a buffer sized by\na user-supplied length (udata_len) without checking a lower bound, then\nset udata_offset to a fixed non-zero value and pass both to a reply\ncallback. The callback bounds-checks the copy with\n\n        if ((udata_len - udata_offset) < len)\n\nBoth fields are u32, so a udata_len smaller than udata_offset makes the\nsubtraction wrap and the check pass, and the following memcpy() writes\npast the allocation. A udata_len of 0 also yields ZERO_SIZE_PTR from\nkzalloc(), which the existing NULL check does not catch.\n\nReject buffers smaller than udata_offset before allocating, so the\ncallback subtraction can no longer underflow.","publishedAt":"2026-08-26T14:37:40.302Z","updatedAt":"2026-10-16T19:26:28.329Z","severity":{"score":8.4,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/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":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"9d00eeb2d27f4cc817c5e408760226d43f811ec6","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"46443eaddebd84c51940857b11787229be169dec","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"91935843f9396a9e45253e2c0d4337ca1371754b","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"cc423f4105fe145b33e1d7cad34245a798358f73","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"3083818e67bcd656965797fbac9a3d6c1d44f78a","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"a3083647747942ea32faf14560d6397ff3068046","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"75fb3151513d7d9f77a8f9545418279b119c06b8","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"d141f087b1af656f055d7c5793a3e87817ba0bbe","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/net/qeth_core_main.c","drivers/s390/net/qeth_l3_main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.26","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.26","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.153","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.105","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.46","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.10","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/net/qeth_core_main.c","drivers/s390/net/qeth_l3_main.c"]}],"references":["https://git.kernel.org/stable/c/9d00eeb2d27f4cc817c5e408760226d43f811ec6","https://git.kernel.org/stable/c/46443eaddebd84c51940857b11787229be169dec","https://git.kernel.org/stable/c/91935843f9396a9e45253e2c0d4337ca1371754b","https://git.kernel.org/stable/c/cc423f4105fe145b33e1d7cad34245a798358f73","https://git.kernel.org/stable/c/3083818e67bcd656965797fbac9a3d6c1d44f78a","https://git.kernel.org/stable/c/a3083647747942ea32faf14560d6397ff3068046","https://git.kernel.org/stable/c/75fb3151513d7d9f77a8f9545418279b119c06b8","https://git.kernel.org/stable/c/d141f087b1af656f055d7c5793a3e87817ba0bbe"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80584.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80584","state":"PUBLISHED","datePublished":"2026-08-26T14:37:40.302Z","dateUpdated":"2026-10-16T19:26:28.329Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.769Z"},"containers":{"cna":{"title":"s390/qeth: validate user buffer length in SNMP and ARP query ioctls","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/qeth: validate user buffer length in SNMP and ARP query ioctls\n\nqeth_snmp_command() and qeth_l3_arp_query() allocate a buffer sized by\na user-supplied length (udata_len) without checking a lower bound, then\nset udata_offset to a fixed non-zero value and pass both to a reply\ncallback. The callback bounds-checks the copy with\n\n        if ((udata_len - udata_offset) < len)\n\nBoth fields are u32, so a udata_len smaller than udata_offset makes the\nsubtraction wrap and the check pass, and the following memcpy() writes\npast the allocation. A udata_len of 0 also yields ZERO_SIZE_PTR from\nkzalloc(), which the existing NULL check does not catch.\n\nReject buffers smaller than udata_offset before allocating, so the\ncallback subtraction can no longer underflow."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"9d00eeb2d27f4cc817c5e408760226d43f811ec6","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"46443eaddebd84c51940857b11787229be169dec","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"91935843f9396a9e45253e2c0d4337ca1371754b","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"cc423f4105fe145b33e1d7cad34245a798358f73","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"3083818e67bcd656965797fbac9a3d6c1d44f78a","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"a3083647747942ea32faf14560d6397ff3068046","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"75fb3151513d7d9f77a8f9545418279b119c06b8","versionType":"git"},{"version":"4a71df50047f0db65ea09b1be155852e81a45eba","status":"affected","lessThan":"d141f087b1af656f055d7c5793a3e87817ba0bbe","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/net/qeth_core_main.c","drivers/s390/net/qeth_l3_main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.26","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.26","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.153","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.105","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.46","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.10","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/net/qeth_core_main.c","drivers/s390/net/qeth_l3_main.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9d00eeb2d27f4cc817c5e408760226d43f811ec6"},{"url":"https://git.kernel.org/stable/c/46443eaddebd84c51940857b11787229be169dec"},{"url":"https://git.kernel.org/stable/c/91935843f9396a9e45253e2c0d4337ca1371754b"},{"url":"https://git.kernel.org/stable/c/cc423f4105fe145b33e1d7cad34245a798358f73"},{"url":"https://git.kernel.org/stable/c/3083818e67bcd656965797fbac9a3d6c1d44f78a"},{"url":"https://git.kernel.org/stable/c/a3083647747942ea32faf14560d6397ff3068046"},{"url":"https://git.kernel.org/stable/c/75fb3151513d7d9f77a8f9545418279b119c06b8"},{"url":"https://git.kernel.org/stable/c/d141f087b1af656f055d7c5793a3e87817ba0bbe"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.4,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires a local ioctl(2) on a qeth netdev (SIOC_QETH_ADP_SET_SNMP_CONTROL or SIOC_QETH_ARP_QUERY_INFO) via socket()->dev_ioctl()->dev_siocdevprivate(); no remote packet or network protocol handler reaches these code paths.\nAC:L - The attacker fully controls udata_len in the ioctl argument; values below the fixed udata_offset (16 for SNMP, 6 for ARP) deterministically underflow the u32 bounds check and cause memcpy() past the kmalloc allocation without races or uncontrollable memory layout.\nPR:N - On affected kernels before CVE-2026-74467, SIOC_QETH_ADP_SET_SNMP_CONTROL had no CAP_NET_ADMIN gate and dev_ioctl() performs no capability check for SIOCDEVPRIVATE, so any unprivileged local user on an IBM Z/LinuxONE LPAR with a qeth interface can reach the overflow.\nUI:N - Exploitation requires only the attacker opening a socket and issuing the crafted ioctl against a qeth interface; no victim login, mount, or other interactive action is needed on a shared mainframe guest.\nS:U - Impact is kernel heap corruption and crash within the local LPAR/kernel security boundary on IBM Z; this does not cross a VM guest-to-host, container, or IOMMU security boundary.\nC:H - The unchecked memcpy() performs a kernel heap out-of-bounds write past a user-sized kmalloc buffer, corrupting adjacent slab objects; per CNA guidance, memory corruption exploitable for information disclosure warrants High confidentiality impact.\nI:H - Integer underflow bypasses the bounds check and memcpy() writes OSA SNMP/ARP response data past the kmalloc allocation end, providing a kernel heap overflow primitive suitable for adjacent-object corruption and privilege escalation.\nA:H - udata_len=0 yields ZERO_SIZE_PTR from kzalloc() (not caught by the NULL check) and memcpy() writes to a fixed low kernel address causing a CPU fault; undersized non-zero lengths corrupt the heap and can trigger kernel oops or panic."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-27T05:02:04.879Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"5.10.266"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"5.15.217"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"6.1.184"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"6.6.153"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"6.12.105"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"6.18.46"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"7.1.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.26","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-80584","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T19:17:53.198738Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T19:26:28.329Z"}}]}}}