{"id":"CVE-2026-23379","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: fix divide by zero in the offload path\n\nOffloading ETS requires computing each class' WRR weight: this is done by\naveraging over the sums of quanta as '…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: fix divide by zero in the offload path\n\nOffloading ETS requires computing each class' WRR weight: this is done by\naveraging over the sums of quanta as '…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-369"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.6.1, < 5.10.253","linux_kernel >= 5.11, < 5.15.203","linux_kernel >= 5.16, < 6.1.167","linux_kernel >= 6.2, < 6.6.130","linux_kernel >= 6.7, < 6.12.77","linux_kernel >= 6.13, < 6.18.17","linux_kernel >= 6.19, < 6.19.7","linux_kernel = 5.6","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.7"],"published":"2026-03-25","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:18:53.343","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-23379","references":[{"url":"https://git.kernel.org/stable/c/3912871344d6a0f1f572a7af2716968182d1e536","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/62015c05878eb9ca448dca7f5a74423d10d40789","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/78b8d2f55a564236435649fbd8bd6a103f30acf5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7dbffffd5761687e168fb2f4aaa7a2c47e067efc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a11ec75a029b3a22b5596f98ce91a3be76a86213","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a6677e23b313cd9fd03690c589c6452cb6fffb97","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/abe1d5cb7fe135c0862c58db32bc29e04cf1c906","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e35626f610f3d2b7953ccddf6a77453da22b3a9e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.0013,"epssPercentile":0.02611,"ingestedAt":"2026-09-08T15:33:26.992Z","slug":"CVE-2026-23379","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: fix divide by zero in the offload path\n\nOffloading ETS requires computing each class' WRR weight: this is done by\naveraging over the sums of quanta as 'q_sum' and 'q_psum'. Using unsigned\nint, the same integer size as the individual DRR quanta, can overflow and\neven cause division by zero, like it happened in the following splat:\n\n Oops: divide error: 0000 [#1] SMP PTI\n CPU: 13 UID: 0 PID: 487 Comm: tc Tainted: G            E       6.19.0-virtme #45 PREEMPT(full)\n Tainted: [E]=UNSIGNED_MODULE\n Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets]\n Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 <41> f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44\n RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246\n RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660\n RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe\n R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe\n R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000\n FS:  00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0\n Call Trace:\n  <TASK>\n  ets_qdisc_change+0x870/0xf40 [sch_ets]\n  qdisc_create+0x12b/0x540\n  tc_modify_qdisc+0x6d7/0xbd0\n  rtnetlink_rcv_msg+0x168/0x6b0\n  netlink_rcv_skb+0x5c/0x110\n  netlink_unicast+0x1d6/0x2b0\n  netlink_sendmsg+0x22e/0x470\n  ____sys_sendmsg+0x38a/0x3c0\n  ___sys_sendmsg+0x99/0xe0\n  __sys_sendmsg+0x8a/0xf0\n  do_syscall_64+0x111/0xf80\n  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n RIP: 0033:0x7f440b81c77e\n Code: 4d 89 d8 e8 d4 bc 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa\n RSP: 002b:00007fff951e4c10 EFLAGS: 00000202 ORIG_RAX: 000000000000002e\n RAX: ffffffffffffffda RBX: 0000000000481820 RCX: 00007f440b81c77e\n RDX: 0000000000000000 RSI: 00007fff951e4cd0 RDI: 0000000000000003\n RBP: 00007fff951e4c20 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff951f4fa8\n R13: 00000000699ddede R14: 00007f440bb01000 R15: 0000000000486980\n  </TASK>\n Modules linked in: sch_ets(E) netdevsim(E)\n ---[ end trace 0000000000000000 ]---\n RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets]\n Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 <41> f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44\n RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246\n RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660\n RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe\n R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe\n R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000\n FS:  00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0\n Kernel panic - not syncing: Fatal exception\n Kernel Offset: 0x30000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)\n ---[ end Kernel panic - not syncing: Fatal exception ]---\n\nFix this using 64-bit integers for 'q_sum' and 'q_psum'.\n\n## Affected\n\n- `linux_kernel >= 5.6.1, < 5.10.253`\n- `linux_kernel >= 5.11, < 5.15.203`\n- `linux_kernel >= 5.16, < 6.1.167`\n- `linux_kernel >= 6.2, < 6.6.130`\n- `linux_kernel >= 6.7, < 6.12.77`\n- `linux_kernel >= 6.13, < 6.18.17`\n- `linux_kernel >= 6.19, < 6.19.7`\n- `linux_kernel = 5.6`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.7`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":221673,"id":"CVE-2026-23379","ts":1792035315189,"field":"cvss","old":null,"new":"5.5"},{"seq":221672,"id":"CVE-2026-23379","ts":1792035315189,"field":"severity","old":"none","new":"medium"}]}