{"id":"CVE-2026-23359","title":"bpf: Fix stack-out-of-bounds write in devmap","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix stack-out-of-bounds write in devmap\n\nget_upper_ifindexes() iterates over all upper devices and writes their\nindices into an array without checking bounds.\n\nAls…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 88df604f0d16a692867582350ce3f2fcd22243f1","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 5000e40acc8d0c36ab709662e32120986ac22e7e","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 8a95fb9df1105b1618872c2846a6c01e3ba20b45","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < d2c31d8e03d05edc16656e5ffe187f0d1da763d7","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 75d474702b2ba8b6bcb26eb3004dbc5e95ffd5d2","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < ca831567908fd3f73cf97d8a6c09a5054697a182","Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < b7bf516c3ecd9a2aae2dc2635178ab87b734fef1","Linux 5.15"],"published":"2026-03-25","updated":"2026-09-08","sourceUpdated":"2026-09-08T08:45:43.846Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23359","references":[{"url":"https://git.kernel.org/stable/c/88df604f0d16a692867582350ce3f2fcd22243f1"},{"url":"https://git.kernel.org/stable/c/5000e40acc8d0c36ab709662e32120986ac22e7e"},{"url":"https://git.kernel.org/stable/c/8a95fb9df1105b1618872c2846a6c01e3ba20b45"},{"url":"https://git.kernel.org/stable/c/d2c31d8e03d05edc16656e5ffe187f0d1da763d7"},{"url":"https://git.kernel.org/stable/c/75d474702b2ba8b6bcb26eb3004dbc5e95ffd5d2"},{"url":"https://git.kernel.org/stable/c/ca831567908fd3f73cf97d8a6c09a5054697a182"},{"url":"https://git.kernel.org/stable/c/b7bf516c3ecd9a2aae2dc2635178ab87b734fef1"}],"tags":["cve.org"],"epss":0.00131,"epssPercentile":0.03109,"ingestedAt":"2026-09-08T15:33:26.992Z","slug":"CVE-2026-23359","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix stack-out-of-bounds write in devmap\n\nget_upper_ifindexes() iterates over all upper devices and writes their\nindices into an array without checking bounds.\n\nAlso the callers assume that the max number of upper devices is\nMAX_NEST_DEV and allocate excluded_devices[1+MAX_NEST_DEV] on the stack,\nbut that assumption is not correct and the number of upper devices could\nbe larger than MAX_NEST_DEV (e.g., many macvlans), causing a\nstack-out-of-bounds write.\n\nAdd a max parameter to get_upper_ifindexes() to avoid the issue.\nWhen there are too many upper devices, return -EOVERFLOW and abort the\nredirect.\n\nTo reproduce, create more than MAX_NEST_DEV(8) macvlans on a device with\nan XDP program attached using BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS.\nThen send a packet to the device to trigger the XDP redirect path.\n\n## Affected\n\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 88df604f0d16a692867582350ce3f2fcd22243f1`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 5000e40acc8d0c36ab709662e32120986ac22e7e`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 8a95fb9df1105b1618872c2846a6c01e3ba20b45`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < d2c31d8e03d05edc16656e5ffe187f0d1da763d7`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < 75d474702b2ba8b6bcb26eb3004dbc5e95ffd5d2`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < ca831567908fd3f73cf97d8a6c09a5054697a182`\n- `Linux >= aeea1b86f9363f3feabb496534d886f082a89f21 < b7bf516c3ecd9a2aae2dc2635178ab87b734fef1`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}