{
  "cveId": "CVE-2021-47126",
  "url": "https://patchblox.com/security/cve/CVE-2021-47126",
  "summary": "CVE-2021-47126 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47126, released March 15, 2024. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  ipv6: Fix KASAN: slab-out-of-bounds Read in fib6...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions  Reported by syzbot: HEAD commit:    90c911ad Merge tag \u0027fixes\u0027 of git://git.kernel.org/pub/scm.. git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master dashboard link: https://syzkaller.appspot.com/bug?extid=123aa35098fd3c000eb7 compiler:       Debian clang version 11.0.1-2  ================================================================== BUG: KASAN: slab-out-of-bounds in fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline] BUG: KASAN: slab-out-of-bounds in fib6_nh_flush_exceptions\u002B0xbd/0x360 net/ipv6/route.c:1732 Read of size 8 at addr ffff8880145c78f8 by task syz-executor.4/17760  CPU: 0 PID: 17760 Comm: syz-executor.4 Not tainted 5.12.0-rc8-syzkaller #0 Call Trace:  \u003CIRQ\u003E  __dump_stack lib/dump_stack.c:79 [inline]  dump_stack\u002B0x202/0x31e lib/dump_stack.c:120  print_address_description\u002B0x5f/0x3b0 mm/kasan/report.c:232  __kasan_report mm/kasan/report.c:399 [inline]  kasan_report\u002B0x15c/0x200 mm/kasan/report.c:416  fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline]  fib6_nh_flush_exceptions\u002B0xbd/0x360 net/ipv6/route.c:1732  fib6_nh_release\u002B0x9a/0x430 net/ipv6/route.c:3536  fib6_info_destroy_rcu\u002B0xcb/0x1c0 net/ipv6/ip6_fib.c:174  rcu_do_batch kernel/rcu/tree.c:2559 [inline]  rcu_core\u002B0x8f6/0x1450 kernel/rcu/tree.c:2794  __do_softirq\u002B0x372/0x7a6 kernel/softirq.c:345  invoke_softirq kernel/softirq.c:221 [inline]  __irq_exit_rcu\u002B0x22c/0x260 kernel/softirq.c:422  irq_exit_rcu\u002B0x5/0x20 kernel/softirq.c:434  sysvec_apic_timer_interrupt\u002B0x91/0xb0 arch/x86/kernel/apic/apic.c:1100  \u003C/IRQ\u003E  asm_sysvec_apic_timer_interrupt\u002B0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:lock_acquire\u002B0x1f6/0x720 kernel/locking/lockdep.c:5515 Code: f6 84 24 a1 00 00 00 02 0f 85 8d 02 00 00 f7 c3 00 02 00 00 49 bd 00 00 00 00 00 fc ff df 74 01 fb 48 c7 44 24 40 0e 36 e0 45 \u003C4b\u003E c7 44 3d 00 00 00 00 00 4b c7 44 3d 09 00 00 00 00 43 c7 44 3d RSP: 0018:ffffc90009e06560 EFLAGS: 00000206 RAX: 1ffff920013c0cc0 RBX: 0000000000000246 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90009e066e0 R08: dffffc0000000000 R09: fffffbfff1f992b1 R10: fffffbfff1f992b1 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920013c0cb4  rcu_lock_acquire\u002B0x2a/0x30 include/linux/rcupdate.h:267  rcu_read_lock include/linux/rcupdate.h:656 [inline]  ext4_get_group_info\u002B0xea/0x340 fs/ext4/ext4.h:3231  ext4_mb_prefetch\u002B0x123/0x5d0 fs/ext4/mballoc.c:2212  ext4_mb_regular_allocator\u002B0x8a5/0x28f0 fs/ext4/mballoc.c:2379  ext4_mb_new_blocks\u002B0xc6e/0x24f0 fs/ext4/mballoc.c:4982  ext4_ext_map_blocks\u002B0x2be3/0x7210 fs/ext4/extents.c:4238  ext4_map_blocks\u002B0xab3/0x1cb0 fs/ext4/inode.c:638  ext4_getblk\u002B0x187/0x6c0 fs/ext4/inode.c:848  ext4_bread\u002B0x2a/0x1c0 fs/ext4/inode.c:900  ext4_append\u002B0x1a4/0x360 fs/ext4/namei.c:67  ext4_init_new_dir\u002B0x337/0xa10 fs/ext4/namei.c:2768  ext4_mkdir\u002B0x4b8/0xc00 fs/ext4/namei.c:2814  vfs_mkdir\u002B0x45b/0x640 fs/namei.c:3819  ovl_do_mkdir fs/overlayfs/overlayfs.h:161 [inline]  ovl_mkdir_real\u002B0x53/0x1a0 fs/overlayfs/dir.c:146  ovl_create_real\u002B0x280/0x490 fs/overlayfs/dir.c:193  ovl_workdir_create\u002B0x425/0x600 fs/overlayfs/super.c:788  ovl_make_workdir\u002B0xed/0x1140 fs/overlayfs/super.c:1355  ovl_get_workdir fs/overlayfs/super.c:1492 [inline]  ovl_fill_super\u002B0x39ee/0x5370 fs/overlayfs/super.c:2035  mount_nodev\u002B0x52/0xe0 fs/super.c:1413  legacy_get_tree\u002B0xea/0x180 fs/fs_context.c:592  vfs_get_tree\u002B0x86/0x270 fs/super.c:1497  do_new_mount fs/namespace.c:2903 [inline]  path_mount\u002B0x196f/0x2be0 fs/namespace.c:3233  do_mount fs/namespace.c:3246 [inline]  __do_sys_mount fs/namespace.c:3454 [inline]  __se_sys_mount\u002B0x2f9/0x3b0 fs/namespace.c:3431  do_syscall_64\u002B0x2d/0x70 arch/x86/entry/common.c:46  entry_SYSCALL_64_after_hwframe\u002B0x44/0xae RIP: 0033:0x4665f9 Code: ff ff c3 66 2e 0f 1f 84  ---truncated---",
  "published": "2024-03-15T21:15:07Z",
  "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",
  "epss": 0.00247,
  "epssPercentile": 0.16055,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47126",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47126",
      "released": "2024-03-15T21:15:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47126",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47126",
      "released": "2024-03-15T21:15:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "5.10.46-1",
      "fix": "DEBIAN-CVE-2021-47126",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47126",
      "released": "2024-03-15T21:15:07Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}