{"id":"CVE-2026-31419","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bonding: fix use-after-free in bond_xmit_broadcast()\n\nbond_xmit_broadcast() reuses the original skb for the last slave\n(determined by bond_is_last_slave()) and clo…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bonding: fix use-after-free in bond_xmit_broadcast()\n\nbond_xmit_broadcast() reuses the original skb for the last slave\n(determined by bond_is_last_slave()) and clo…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416","CWE-416"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.10.94, < 5.11","linux_kernel >= 5.15.17, < 5.16","linux_kernel >= 5.16.3, < 5.17","linux_kernel >= 5.17, < 6.12.86","linux_kernel >= 6.13, < 6.18.22","linux_kernel >= 6.19, < 6.19.12","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.12"],"published":"2026-04-13","updated":"2026-07-04","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31419","references":[{"url":"https://git.kernel.org/stable/c/2884bf72fb8f03409e423397319205de48adca16","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2de5c8eea0a9db99dae7c36f4b541b74b41d3a04","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a0f661918edc79d7a75e468128af8d41e2a1a83a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d4cc7e4c80b1634c7b1497574a2fdb18df6c026c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f5b94654a4a19891a8108d66ef166de6c028c6cd","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://access.redhat.com/errata/RHSA-2026:13566","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:19521","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:21209","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:22334","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:22900","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:22940","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:23224","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:25191","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:25217","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:27353","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:27354","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-31419","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2457829","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31419.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}],"tags":["nvd"],"epss":0.00181,"epssPercentile":0.06824,"ingestedAt":"2026-07-04T12:56:09.352Z","slug":"CVE-2026-31419","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: bonding: fix use-after-free in bond_xmit_broadcast()\n\nbond_xmit_broadcast() reuses the original skb for the last slave\n(determined by bond_is_last_slave()) and clones it for others.\nConcurrent slave enslave/release can mutate the slave list during\nRCU-protected iteration, changing which slave is \"last\" mid-loop.\nThis causes the original skb to be double-consumed (double-freed).\n\nReplace the racy bond_is_last_slave() check with a simple index\ncomparison (i + 1 == slaves_count) against the pre-snapshot slave\ncount taken via READ_ONCE() before the loop.  This preserves the\nzero-copy optimization for the last slave while making the \"last\"\ndetermination stable against concurrent list mutations.\n\nThe UAF can trigger the following crash:\n\n==================================================================\nBUG: KASAN: slab-use-after-free in skb_clone\nRead of size 8 at addr ffff888100ef8d40 by task exploit/147\n\nCPU: 1 UID: 0 PID: 147 Comm: exploit Not tainted 7.0.0-rc3+ #4 PREEMPTLAZY\nCall Trace:\n <TASK>\n dump_stack_lvl (lib/dump_stack.c:123)\n print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)\n kasan_report (mm/kasan/report.c:597)\n skb_clone (include/linux/skbuff.h:1724 include/linux/skbuff.h:1792 include/linux/skbuff.h:3396 net/core/skbuff.c:2108)\n bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5334)\n bond_start_xmit (drivers/net/bonding/bond_main.c:5567 drivers/net/bonding/bond_main.c:5593)\n dev_hard_start_xmit (include/linux/netdevice.h:5325 include/linux/netdevice.h:5334 net/core/dev.c:3871 net/core/dev.c:3887)\n __dev_queue_xmit (include/linux/netdevice.h:3601 net/core/dev.c:4838)\n ip6_finish_output2 (include/net/neighbour.h:540 include/net/neighbour.h:554 net/ipv6/ip6_output.c:136)\n ip6_finish_output (net/ipv6/ip6_output.c:208 net/ipv6/ip6_output.c:219)\n ip6_output (net/ipv6/ip6_output.c:250)\n ip6_send_skb (net/ipv6/ip6_output.c:1985)\n udp_v6_send_skb (net/ipv6/udp.c:1442)\n udpv6_sendmsg (net/ipv6/udp.c:1733)\n __sys_sendto (net/socket.c:730 net/socket.c:742 net/socket.c:2206)\n __x64_sys_sendto (net/socket.c:2209)\n do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)\n </TASK>\n\nAllocated by task 147:\n\nFreed by task 147:\n\nThe buggy address belongs to the object at ffff888100ef8c80\n which belongs to the cache skbuff_head_cache of size 224\nThe buggy address is located 192 bytes inside of\n freed 224-byte region [ffff888100ef8c80, ffff888100ef8d60)\n\nMemory state around the buggy address:\n ffff888100ef8c00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc\n ffff888100ef8c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n>ffff888100ef8d00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc\n                                                    ^\n ffff888100ef8d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb\n ffff888100ef8e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n==================================================================\n\n## Affected\n\n- `linux_kernel >= 5.10.94, < 5.11`\n- `linux_kernel >= 5.15.17, < 5.16`\n- `linux_kernel >= 5.16.3, < 5.17`\n- `linux_kernel >= 5.17, < 6.12.86`\n- `linux_kernel >= 6.13, < 6.18.22`\n- `linux_kernel >= 6.19, < 6.19.12`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.12`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}