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Unscored CVE-2025-39980 EUVD-2025-34592GHSA-9g6c-7w9m-p2mh

nexthop: Forbid FDB status change while nexthop is in a group

Published Oct 15, 2025 · Updated Nov 10, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: kernel Package: linux Package: linux Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.15 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.8 Package: linux-aws-6.14 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-fips Package: linux-azure Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.15 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fips Package: linux-azure-nvidia Package: linux-azure-nvidia-6.14 Package: linux-bluefield Package: linux-fips Package: linux-gcp Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.15 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-fips Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.15 Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.15 Package: linux-hwe-5.19 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-edge Package: linux-ibm Package: linux-ibm-5.15 Package: linux-ibm-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-intel-iotg Package: linux-intel-iotg-5.15 Package: linux-kvm Package: linux-lowlatency Package: linux-lowlatency-hwe-5.15 Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.11 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-lowlatency-hwe-6.8 Package: linux-nvidia Package: linux-nvidia-6.11 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-6.8 Package: linux-nvidia-lowlatency Package: linux-nvidia-tegra Package: linux-nvidia-tegra-5.15 Package: linux-nvidia-tegra-igx Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oem-6.11 Package: linux-oem-6.14 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.15 Package: linux-oracle-5.3 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.8 Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.15 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-riscv-6.14 Package: linux-riscv-6.5 Package: linux-riscv-6.8 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Package: linux-xilinx Package: linux-xilinx-zynqmp Platform: Linux Ecosystem: Azure Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

In the Linux kernel, the following vulnerability has been resolved:

nexthop: Forbid FDB status change while nexthop is in a group

The kernel forbids the creation of non-FDB nexthop groups with FDB
nexthops:

# ip nexthop add id 1 via 192.0.2.1 fdb
# ip nexthop add id 2 group 1
Error: Non FDB nexthop group cannot have fdb nexthops.

And vice versa:

# ip nexthop add id 3 via 192.0.2.2 dev dummy1
# ip nexthop add id 4 group 3 fdb
Error: FDB nexthop group can only have fdb nexthops.

However, as long as no routes are pointing to a non-FDB nexthop group,
the kernel allows changing the type of a nexthop from FDB to non-FDB and
vice versa:

# ip nexthop add id 5 via 192.0.2.2 dev dummy1
# ip nexthop add id 6 group 5
# ip nexthop replace id 5 via 192.0.2.2 fdb
# echo $?
0

This configuration is invalid and can result in a NPD [1] since FDB
nexthops are not associated with a nexthop device:

# ip route add 198.51.100.1/32 nhid 6
# ping 198.51.100.1

Fix by preventing nexthop FDB status change while the nexthop is in a
group:

# ip nexthop add id 7 via 192.0.2.2 dev dummy1
# ip nexthop add id 8 group 7
# ip nexthop replace id 7 via 192.0.2.2 fdb
Error: Cannot change nexthop FDB status while in a group.

[1]
BUG: kernel NULL pointer dereference, address: 00000000000003c0
[...]
Oops: Oops: 0000 [#1] SMP
CPU: 6 UID: 0 PID: 367 Comm: ping Not tainted 6.17.0-rc6-virtme-gb65678cacc03 #1 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
RIP: 0010:fib_lookup_good_nhc+0x1e/0x80
[...]
Call Trace:
<TASK>
fib_table_lookup+0x541/0x650
ip_route_output_key_hash_rcu+0x2ea/0x970
ip_route_output_key_hash+0x55/0x80
__ip4_datagram_connect+0x250/0x330
udp_connect+0x2b/0x60
__sys_connect+0x9c/0xd0
__x64_sys_connect+0x18/0x20
do_syscall_64+0xa4/0x2a0
entry_SYSCALL_64_after_hwframe+0x4b/0x53

Affected products

VendorProductAffectedFixed
Linux Linux 5.8 5.10.245

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 linux 6.16.10-1 —
Debian 13 linux 6.12.57-1 —
Debian 12 linux 6.1.158-1 DSA-6053-1
Debian 11 linux 5.10.247-1 DLA-4404-1
Debian 11 linux-6.1 6.1.158-1~deb11u1 DLA-4379-1
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1017.21 —
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield 5.15.0-1084.86 —
Ubuntu 25.10 linux 6.17.0-6.6 —
Ubuntu 25.10 linux-aws +2 6.17.0-1003.3 —
Ubuntu 25.10 linux-azure 6.17.0-1006.6 —
Ubuntu 25.10 linux-azure-fde No fix yet —
Ubuntu 25.10 linux-raspi 6.17.0-1004.4 —
Ubuntu 25.10 linux-realtime 6.17.0-1002.3 —
Ubuntu 25.10 linux-riscv 6.17.0-6.6.1 —
Ubuntu 24.04 LTS linux 6.8.0-106.106 USN-8095-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1050.53 USN-8095-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1051.57 USN-8125-1
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1058.65 —
Ubuntu 24.04 LTS linux-azure-nvidia 6.8.0-1039.42 —
Ubuntu 24.04 LTS linux-gcp 6.8.0-1052.55 USN-8095-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1048.53 USN-8095-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1035.38 USN-8095-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1049.49 USN-8095-1
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-106.106.1 USN-8095-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1049.52 USN-8100-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1049.52.1 USN-8100-1
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1020.20 —
Ubuntu 24.04 LTS linux-oracle 6.8.0-1047.48 USN-8095-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1050.54 USN-8095-5
Ubuntu 24.04 LTS linux-riscv +18 No fix yet —
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1028.29 USN-8261-1
Ubuntu 22.04 LTS linux +1 5.15.0-170.180 USN-8033-1
Ubuntu 22.04 LTS linux-aws 5.15.0-1100.107 USN-8033-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1050.53~22.04.1 USN-8095-4
Ubuntu 22.04 LTS linux-azure 5.15.0-1109.118 USN-8163-2
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1051.57~22.04.1 USN-8126-1
Ubuntu 22.04 LTS linux-azure-fde 5.15.0-1109.118.1 —
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1058.65~22.04.1 —
Ubuntu 22.04 LTS linux-gcp 5.15.0-1100.109 USN-8033-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1052.55~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-gke 5.15.0-1096.102 USN-8033-1
Ubuntu 22.04 LTS linux-gkeop 5.15.0-1083.91 USN-8033-1
Ubuntu 22.04 LTS linux-hwe-6.8 +1 6.8.0-106.106~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-ibm 5.15.0-1094.97 USN-8033-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1049.49~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-intel-iotg 5.15.0-1095.101 USN-8033-8
Ubuntu 22.04 LTS linux-kvm 5.15.0-1092.97 USN-8033-5
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-106.106.1~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1095.96 USN-8033-6
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1049.52~22.04.1 USN-8100-1
Ubuntu 22.04 LTS linux-nvidia-tegra 5.15.0-1052.52 USN-8034-1
Ubuntu 22.04 LTS linux-nvidia-tegra-igx 5.15.0-1041.41 USN-8034-2
Ubuntu 22.04 LTS linux-oracle 5.15.0-1097.103 USN-8033-5
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1047.48~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-raspi 5.15.0-1097.100 USN-8141-1
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 22.04 LTS linux-xilinx-zynqmp 5.15.0-1064.68 USN-8033-7
Show 9 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 20.04 LTS linux-gke +28 No fix yet —
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-raspi-realtime 6.8.0-2040.41 USN-8095-5
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1045.46 USN-8095-3
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-intel-iot-realtime 5.15.0-1092.94 USN-8033-2
Ubuntu Pro Realtime 22.04 LTS linux-realtime 5.15.0-1099.108 USN-8033-2
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1045.46~22.04.1 USN-8095-3
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1050.53+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1052.58+fips1 USN-8165-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-106.106+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1052.55+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 22.04 LTS linux-aws-fips 5.15.0-1100.107+fips1 USN-8033-3
Ubuntu Pro FIPS-updates 22.04 LTS linux-azure-fips 5.15.0-1109.118+fips1 USN-8163-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-fips 5.15.0-170.180+fips1 USN-8033-3
Ubuntu Pro FIPS-updates 22.04 LTS linux-gcp-fips 5.15.0-1100.109+fips1 USN-8033-3
Ubuntu Pro FIPS-preview 22.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro 20.04 LTS linux-aws-5.15 5.15.0-1100.107~20.04.2 USN-8033-4
Ubuntu Pro 20.04 LTS linux-azure-5.15 5.15.0-1110.119~20.04.1 USN-8243-1
Ubuntu Pro 20.04 LTS linux-gcp-5.15 5.15.0-1100.109~20.04.1 USN-8033-5
Ubuntu Pro 20.04 LTS linux-hwe-5.15 5.15.0-170.180~20.04.3 USN-8033-1
Ubuntu Pro 20.04 LTS linux-ibm-5.15 5.15.0-1094.97~20.04.1 USN-8033-1
Ubuntu Pro 20.04 LTS linux-intel-iotg-5.15 5.15.0-1095.101~20.04.1 USN-8033-7
Ubuntu Pro 20.04 LTS linux-lowlatency-hwe-5.15 5.15.0-170.180~20.04.1 USN-8033-1
Ubuntu Pro 20.04 LTS linux-nvidia-tegra-5.15 5.15.0-1052.52~20.04.2 USN-8034-1
Ubuntu Pro 20.04 LTS linux-oracle-5.15 5.15.0-1097.103~20.04.1 USN-8033-5
Ubuntu Pro 20.04 LTS linux-riscv-5.15 5.15.0-1095.99~20.04.1 —
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +5 6.4.0-150700.53.25.1 SUSE-SU-2025:4393-1
SLES 15 SP7 kernel-azure +2 6.4.0-150700.20.21.1 SUSE-SU-2025:4517-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.25.1.150700.17.17.1 SUSE-SU-2025:4393-1
SLES 15 SP7 kernel-docs 6.4.0-150700.53.25.2 SUSE-SU-2025:4393-1
SLES 15 SP6 kernel-64kb +3 6.4.0-150600.23.81.3 SUSE-SU-2025:4422-1
SLES 15 SP6 kernel-azure +2 6.4.0-150600.8.58.1 SUSE-SU-2025:4505-1
SLES 15 SP6 kernel-default-base 6.4.0-150600.23.81.3.150600.12.36.3 SUSE-SU-2025:4422-1
SLES 15 SP6 kernel-docs +1 6.4.0-150600.23.81.1 SUSE-SU-2025:4422-1
SLES 15 SP6 kernel-source 6.4.0-150600.23.81.2 SUSE-SU-2025:4422-1
Show 9 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +7 6.12.0-160000.8.1 SUSE-SU-2026:20015-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.8.1.160000.2.5 SUSE-SU-2026:20015-1
SLES 16.0 kernel-64kb +7 6.12.0-160000.8.1 SUSE-SU-2026:20021-1, SUSE-SU-2026:20015-1
SLES 16.0 kernel-default-base 6.12.0-160000.8.1.160000.2.5 SUSE-SU-2026:20015-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.8.1.160000.2.5 SUSE-SU-2026:20012-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.8.1 SUSE-SU-2026:20562-1, SUSE-SU-2026:20012-1
SLE Micro 6.1 kernel-default-base 6.4.0-38.1.21.15 SUSE-SU-2026:20496-1
SLE Micro 6.1 kernel-rt +1 6.4.0-39.1 SUSE-SU-2026:20059-1
SLE Micro 6.1 kernel-source +2 6.4.0-38.1 SUSE-SU-2026:20496-1
SLE Micro 6.0 kernel-default-base 6.4.0-38.1.21.15 SUSE-SU-2026:20473-1
SLE Micro 6.0 kernel-rt +1 6.4.0-39.1 SUSE-SU-2026:20039-1
SLE Micro 6.0 kernel-source +2 6.4.0-38.1 SUSE-SU-2026:20473-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.25.1 SUSE-SU-2025:4393-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_7 1-150700.1.3.1 SUSE-SU-2025:4516-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_7 1-150700.15.3.1 SUSE-SU-2025:4393-1
SLE Live Patching 15 SP6 kernel-default 6.4.0-150600.23.81.3 SUSE-SU-2025:4422-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6-RT_Update_18 1-150600.1.3.1 SUSE-SU-2025:4521-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_18 1-150600.13.3.3 SUSE-SU-2025:4422-1
SUSE Real Time Module 15 SP7 kernel-rt +2 6.4.0-150700.7.25.1 SUSE-SU-2025:4516-1
SUSE Real Time Module 15 SP6 kernel-rt +3 6.4.0-150600.10.61.1 SUSE-SU-2025:4521-1
ReleasePackageFixed inAdvisory
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.8.1.160000.2.5 openSUSE-SU-2025:20172-1
openSUSE Leap 16.0 kernel-rt +10 6.12.0-160000.8.1 openSUSE-SU-2025:20172-1
openSUSE Leap 15.6 dtb-aarch64 +3 6.4.0-150600.23.81.1 SUSE-SU-2025:4422-1
openSUSE Leap 15.6 kernel-64kb +5 6.4.0-150600.23.81.3 SUSE-SU-2025:4422-1
openSUSE Leap 15.6 kernel-azure +2 6.4.0-150600.8.58.1 SUSE-SU-2025:4505-1
openSUSE Leap 15.6 kernel-default-base 6.4.0-150600.23.81.3.150600.12.36.3 SUSE-SU-2025:4422-1
openSUSE Leap 15.6 kernel-rt +3 6.4.0-150600.10.61.1 SUSE-SU-2025:4521-1
openSUSE Leap 15.6 kernel-source 6.4.0-150600.23.81.2 SUSE-SU-2025:4422-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.12.53-69.119 +1 1:1.0-0.amzn2023 ALAS2023-2025-1254, ALAS2023-2025-1223
Amazon Linux 2023 perf +14 1:6.1.155-176.282.amzn2023 ALAS2023-2025-1223
Amazon Linux 2023 perf6.12 +14 1:6.12.53-69.119.amzn2023 ALAS2023-2025-1254

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.112.1-1 —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 8 bpftool +18 5.15.0-315.196.5.1.el9uek ELSA-2025-28048

Advisories 50

References