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Unscored Public exploit CVE-2025-68325 EUVD-2025-204267GHSA-vwv2-fc39-c5f6

net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop

Published Dec 18, 2025 · Updated May 23, 2026 · Assigned by Linux

Vendor: Linux Product: Linux 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-6.17 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-6.17 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-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fips 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-6.17 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-6.17 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-6.17 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-6.17 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-6.17 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-6.17 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-6.17 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: Debian Ecosystem: Ubuntu

Description

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

net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop

In cake_drop(), qdisc_tree_reduce_backlog() is used to update the qlen
and backlog of the qdisc hierarchy. Its caller, cake_enqueue(), assumes
that the parent qdisc will enqueue the current packet. However, this
assumption breaks when cake_enqueue() returns NET_XMIT_CN: the parent
qdisc stops enqueuing current packet, leaving the tree qlen/backlog
accounting inconsistent. This mismatch can lead to a NULL dereference
(e.g., when the parent Qdisc is qfq_qdisc).

This patch computes the qlen/backlog delta in a more robust way by
observing the difference before and after the series of cake_drop()
calls, and then compensates the qdisc tree accounting if cake_enqueue()
returns NET_XMIT_CN.

To ensure correct compensation when ACK thinning is enabled, a new
variable is introduced to keep qlen unchanged.

Affected products

VendorProductAffectedFixed
Linux Linux 5.10.241 – < 5.10.248, 5.15.190 – < 5.15.198, 6.1.149 – < 6.1.160, 6.6.103 – < 6.6.120, 6.12.44 – < 6.12.63, 5.4.297 – < 5.5, 6.16.4 – < 6.17, 6.17 5.10.248

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 6.17.13-1 —
Debian 13 linux 6.12.63-1 —
Debian 12 linux 6.1.162-1 DSA-6127-1
Debian 11 linux 5.10.249-1 DLA-4475-1
Debian 11 linux-6.1 6.1.162-1~deb11u1 DLA-4476-1
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1017.21 —
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield 5.15.0-1086.88 —
Ubuntu 25.10 linux 6.17.0-19.19 USN-8094-1
Ubuntu 25.10 linux-aws +2 6.17.0-1009.9 USN-8094-1
Ubuntu 25.10 linux-azure +1 6.17.0-1010.10 USN-8094-5, USN-8094-4
Ubuntu 25.10 linux-azure-fde No fix yet —
Ubuntu 25.10 linux-realtime 6.17.0-1008.9 USN-8094-2
Ubuntu 25.10 linux-riscv 6.17.0-19.19.1 —
Ubuntu 24.04 LTS linux 6.8.0-110.110 USN-8179-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1052.55 USN-8179-1
Ubuntu 24.04 LTS linux-aws-6.17 6.17.0-1009.9~24.04.2 USN-8094-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1054.60 USN-8258-1
Ubuntu 24.04 LTS linux-azure-6.17 6.17.0-1010.10~24.04.1 USN-8094-4
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1058.65 —
Ubuntu 24.04 LTS linux-gcp 6.8.0-1054.57 USN-8179-1
Ubuntu 24.04 LTS linux-gcp-6.17 6.17.0-1009.9~24.04.3 USN-8094-2
Ubuntu 24.04 LTS linux-gke 6.8.0-1050.56 USN-8179-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1037.40 USN-8179-1
Ubuntu 24.04 LTS linux-hwe-6.17 6.17.0-19.19~24.04.2 USN-8094-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1051.51 USN-8179-1
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-110.110.1 USN-8179-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1051.54 USN-8185-1
Ubuntu 24.04 LTS linux-nvidia-6.17 6.17.0-1018.18 —
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1051.54.1 USN-8185-2
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1022.22 USN-8265-1
Ubuntu 24.04 LTS linux-oem-6.17 6.17.0-1017.17 USN-8152-1
Ubuntu 24.04 LTS linux-oracle 6.8.0-1049.50 USN-8203-1
Ubuntu 24.04 LTS linux-oracle-6.17 6.17.0-1009.9~24.04.1 USN-8094-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1052.56 USN-8179-3
Ubuntu 24.04 LTS linux-riscv +10 No fix yet —
Ubuntu 24.04 LTS linux-riscv-6.17 6.17.0-19.19.1~24.04.1 —
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1028.29 USN-8261-1
Ubuntu 22.04 LTS linux +1 5.15.0-173.183 USN-8096-1
Ubuntu 22.04 LTS linux-aws 5.15.0-1103.110 USN-8096-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1052.55~22.04.1 USN-8179-1
Ubuntu 22.04 LTS linux-azure 5.15.0-1109.118 USN-8163-2
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1059.65~22.04.1 USN-8440-1
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 5.15.0-1103.112 USN-8096-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1054.57~22.04.1 USN-8179-4
Ubuntu 22.04 LTS linux-gke 5.15.0-1099.105 USN-8096-3
Ubuntu 22.04 LTS linux-gkeop 5.15.0-1086.94 USN-8096-1
Ubuntu 22.04 LTS linux-hwe-6.8 +1 6.8.0-110.110~22.04.1 USN-8179-3
Ubuntu 22.04 LTS linux-ibm +1 5.15.0-1097.100 USN-8141-1, USN-8096-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1051.51~22.04.1 USN-8179-3
Ubuntu 22.04 LTS linux-intel-iotg 5.15.0-1098.104 USN-8096-1
Ubuntu 22.04 LTS linux-kvm 5.15.0-1095.100 USN-8096-1
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-110.110.1~22.04.1 USN-8179-1
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1098.99 USN-8096-1
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1051.54~22.04.1 USN-8185-1
Ubuntu 22.04 LTS linux-nvidia-tegra 5.15.0-1055.55 USN-8096-1
Ubuntu 22.04 LTS linux-nvidia-tegra-igx 5.15.0-1044.44 USN-8096-5
Ubuntu 22.04 LTS linux-oracle 5.15.0-1100.106 USN-8096-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1049.50~22.04.1 USN-8203-1
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 22.04 LTS linux-xilinx-zynqmp 5.15.0-1067.71 USN-8096-1
Show 8 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 6.8.0-2042.43 USN-8204-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1047.48 USN-8184-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.17 6.17.0-1008.9~24.04.1 USN-8094-3
Ubuntu Pro Realtime 22.04 LTS linux-intel-iot-realtime 5.15.0-1094.96 USN-8116-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime 5.15.0-1102.111 USN-8096-4
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1047.48~22.04.1 USN-8184-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1052.55+fips1 USN-8179-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1053.59+fips1 —
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-110.110+fips2 USN-8179-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1054.57+fips1 USN-8179-2
Ubuntu Pro FIPS-updates 22.04 LTS linux-aws-fips 5.15.0-1103.110+fips1 USN-8096-2
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 5.15.0-173.183+fips1 USN-8096-2
Ubuntu Pro FIPS-updates 22.04 LTS linux-gcp-fips 5.15.0-1103.112+fips1 USN-8096-2
Ubuntu Pro 20.04 LTS linux-aws-5.15 5.15.0-1103.110~20.04.1 USN-8096-3
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 5.15.0-1103.112~20.04.1 USN-8096-3
Ubuntu Pro 20.04 LTS linux-hwe-5.15 +1 5.15.0-173.183~20.04.1 USN-8096-3
Ubuntu Pro 20.04 LTS linux-ibm-5.15 5.15.0-1097.100~20.04.1 USN-8096-1
Ubuntu Pro 20.04 LTS linux-intel-iotg-5.15 5.15.0-1098.104~20.04.1 USN-8096-3
Ubuntu Pro 20.04 LTS linux-nvidia-tegra-5.15 5.15.0-1055.55~20.04.1 USN-8096-1
Ubuntu Pro 20.04 LTS linux-oracle-5.15 5.15.0-1100.106~20.04.1 USN-8096-3
Ubuntu Pro 20.04 LTS linux-riscv-5.15 5.15.0-1097.101~20.04.1 —
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +6 6.4.0-150700.53.31.1 SUSE-SU-2026:0447-1
SLES 15 SP7 kernel-azure +2 6.4.0-150700.20.27.1 SUSE-SU-2026:0472-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.31.1.150700.17.21.1 SUSE-SU-2026:0447-1
Show 7 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.26.1 SUSE-SU-2026:20599-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.26.1.160000.2.7 SUSE-SU-2026:20599-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.26.1 SUSE-SU-2026:20615-1, SUSE-SU-2026:20599-1
SLES 16.0 kernel-default-base 6.12.0-160000.26.1.160000.2.7 SUSE-SU-2026:20599-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.26.1.160000.2.7 SUSE-SU-2026:20555-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.26.1 SUSE-SU-2026:20570-1, SUSE-SU-2026:20555-1
SLE Micro 6.1 kernel-default-base 6.4.0-39.1.21.16 SUSE-SU-2026:20498-1
SLE Micro 6.1 kernel-rt +1 6.4.0-40.1 SUSE-SU-2026:20876-1
SLE Micro 6.1 kernel-source +2 6.4.0-39.1 SUSE-SU-2026:20498-1
SLE Micro 6.0 kernel-default-base 6.4.0-39.1.21.16 SUSE-SU-2026:20477-1
SLE Micro 6.0 kernel-rt +1 6.4.0-40.1 SUSE-SU-2026:20845-1
SLE Micro 6.0 kernel-source +2 6.4.0-39.1 SUSE-SU-2026:20477-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.31.1 SUSE-SU-2026:0447-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_9 1-150700.1.3.2 SUSE-SU-2026:0587-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_9 1-150700.15.3.1 SUSE-SU-2026:0447-1
SUSE Real Time Module 15 SP7 kernel-rt 6.4.0-150700.7.31.2 SUSE-SU-2026:0587-1
SUSE Real Time Module 15 SP7 kernel-syms-rt +1 6.4.0-150700.7.31.1 SUSE-SU-2026:0587-1
ReleasePackageFixed inAdvisory
openSUSE Tumbleweed kernel-source 6.18.2-1.1 openSUSE-SU-2025:15836-1
openSUSE Tumbleweed kernel-source-longterm 6.18.16-1.1 openSUSE-SU-2026:10301-1
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.26.1.160000.2.7 openSUSE-SU-2026:20287-1
openSUSE Leap 16.0 kernel-rt +11 6.12.0-160000.26.1 openSUSE-SU-2026:20287-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.12.63-84.121 +1 1:1.0-0.amzn2023 ALAS2023-2026-1494, ALAS2023-2026-1430
Amazon Linux 2023 perf +14 1:6.1.161-183.298.amzn2023 ALAS2023-2026-1494
Amazon Linux 2023 perf6.12 +14 1:6.12.63-84.121.amzn2023 ALAS2023-2026-1430

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 9 kernel-uek +34 6.12.0-108.64.6.3.el10uek ELSA-2026-50112
Oracle Linux 8 bpftool +18 5.15.0-317.197.5.1.el9uek ELSA-2026-50113

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 50

References