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TI-2024-27269 Aliases CVE-2024-40905GHSA-p46c-p6jp-xfpq

ipv6: fix possible race in __fib6_drop_pcpu_from()

Priority LOW 21CWE-476Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 fixed, 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix possible race in __fib6_drop_pcpu_from() syzbot found a race in __fib6_drop_pcpu_from() [1] If compiler reads more than once (*ppcpu_rt), second read could read NULL, if another cpu clears the value in rt6_get_pcpu_route(). Add a READ_ONCE() to prevent this race. Also add rcu_read_lock()/rcu_read_unlock() because we rely on RCU protection while dereferencing pcpu_rt. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097] CPU: 0 PID: 7543 Comm: kworker/u8:17 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: netns cleanup_net RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10a/0x370 net/ipv6/ip6_fib.c:984 Code: f8 48 c1 e8 03 80 3c 28 00 0f 85 16 02 00 00 4d 8b 3f 4d 85 ff 74 31 e8 74 a7 fa f7 49 8d bf 90 00 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 1e 02 00 00 49 8b 87 90 00 00 00 48 8b 0c 24 48 RSP: 0018:ffffc900040df070 EFLAGS: 00010206 RAX: 0000000000000012 RBX: 0000000000000001 RCX: ffffffff89932e16 RDX: ffff888049dd1e00 RSI: ffffffff89932d7c RDI: 0000000000000091 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000007 R10: 0000000000000001 R11: 0000000000000006 R12: ffff88807fa080b8 R13: fffffbfff1a9a07d R14: ffffed100ff41022 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32c26000 CR3: 000000005d56e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __fib6_drop_pcpu_from net/ipv6/ip6_fib.c:966 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1027 [inline] fib6_purge_rt+0x7f2/0x9f0 net/ipv6/ip6_fib.c:1038 fib6_del_route net/ipv6/ip6_fib.c:1998 [inline] fib6_del+0xa70/0x17b0 net/ipv6/ip6_fib.c:2043 fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2205 fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2127 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2175 fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2255 __fib6_clean_all+0x100/0x2d0 net/ipv6/ip6_fib.c:2271 rt6_sync_down_dev net/ipv6/route.c:4906 [inline] rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911 addrconf_ifdown.isra.0+0x117/0x1b40 net/ipv6/addrconf.c:3855 addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_close_many+0x333/0x6a0 net/core/dev.c:1585 unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193 unregister_netdevice_many net/core/dev.c:11276 [inline] default_device_exit_batch+0x85b/0xae0 net/core/dev.c:11759 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0027 19th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.4.279, 5.10.221, 5.15.162 +4Red Hat: 1 advisoryRed Hat: 5 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.2 and later5.4.279, 5.10.221, 5.15.162, 6.1.95, 6.6.35, 6.9.6, 6.10Patch availableCNA
  • Linux VendorLinux Affected 4.2 and later Fixed in 5.4.279, 5.10.221, 5.15.162, 6.1.95, 6.6.35, 6.9.6, 6.10 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*4.2 to before 5.4.279; 5.5 to before 5.10.221; 5.11 to before 5.15.162; 5.16 to before 6.1.95; 6.2 to before 6.6.35; 6.7 to before 6.9.6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.10:rc1:*:*:*:*:*:*6.10 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.10:rc2:*:*:*:*:*:*6.10 rc2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.2 to before 5.4.279; 5.5 to before 5.10.221; 5.11 to before 5.15.162; 5.16 to before 6.1.95; 6.2 to before 6.6.35; 6.7 to before 6.9.6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.10:rc1:*:*:*:*:*:* Versions 6.10 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.10:rc2:*:*:*:*:*:* Versions 6.10 rc2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.4.279, 5.10.221, 5.15.162, 6.1.95, 6.6.35, 6.9.6, 6.10

Red Hat 1 advisory

  • RHSA-2024:5928 Released 2024-08-28 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-427.33.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.33.1.el9_4, kernel-64k-devel-5.14.0-427.33.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.3.0-427.33.1.el9_4, kernel-5.14.0-427.33.1.el9_4, kernel-64k-5.14.0-427.33.1.el9_4 +29
    • Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-427.33.1.el9_4, libperf-5.14.0-427.33.1.el9_4
    • Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-427.33.1.el9_4, kernel-rt-core-5.14.0-427.33.1.el9_4, kernel-rt-debug-5.14.0-427.33.1.el9_4 +11
    • Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-427.33.1.el9_4, kernel-rt-core-5.14.0-427.33.1.el9_4, kernel-rt-debug-5.14.0-427.33.1.el9_4 +9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 9AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:5928
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2024:5928
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2024:5928
Red Hat Enterprise Linux NFV (v. 9)Fixed RHSA-2024:5928
Red Hat Enterprise Linux RT (v. 9)Fixed RHSA-2024:5928

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-40905
  2. 2026-10-03 Alias added: GHSA-p46c-p6jp-xfpq
  3. 2026-10-29 Affected versions changed · Red Hat

References

Patch 7

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences