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High · 7.5 CVE-2026-46306 EUVD-2026-35171GHSA-vm8v-fr63-mfh4

flow_dissector: do not dissect PPPoE PFC frames

Published Jun 8, 2026 · 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-5.19 Package: linux-aws-5.3 Package: linux-aws-5.8 Package: linux-aws-6.14 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-5.19 Package: linux-azure-5.3 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-7.0 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-fde-7.0 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-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-7.0 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-5.19 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-7.0 Package: linux-hwe-edge Package: linux-ibm Package: linux-ibm-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-lowlatency 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-7.0 Package: linux-nvidia-bos Package: linux-nvidia-lowlatency Package: linux-nvidia-tegra 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-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oem-7.0 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.3 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-oracle-7.0 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 Package: linux-realtime-6.8 Package: linux-riscv Package: linux-riscv-5.11 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-riscv-7.0 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Package: linux-xilinx Platform: Linux Ecosystem: Azure Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

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

flow_dissector: do not dissect PPPoE PFC frames

RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT
RECOMMENDED for PPPoE. In practice, pppd does not support negotiating
PFC for PPPoE sessions, and the flow dissector driver has assumed an
uncompressed frame until the blamed commit.

During the review process of that commit [1], support for PFC is
suggested. However, having a compressed (1-byte) protocol field means
the subsequent PPP payload is shifted by one byte, causing 4-byte
misalignment for the network header and an unaligned access exception
on some architectures.

The exception can be reproduced by sending a PPPoE PFC frame to an
ethernet interface of a MIPS board, with RPS enabled, even if no PPPoE
session is active on that interface:

$ 0 : 00000000 80c40000 00000000 85144817
$ 4 : 00000008 00000100 80a75758 81dc9bb8
$ 8 : 00000010 8087ae2c 0000003d 00000000
$12 : 000000e0 00000039 00000000 00000000
$16 : 85043240 80a75758 81dc9bb8 00006488
$20 : 0000002f 00000007 85144810 80a70000
$24 : 81d1bda0 00000000
$28 : 81dc8000 81dc9aa8 00000000 805ead08
Hi : 00009d51
Lo : 2163358a
epc : 805e91f0 __skb_flow_dissect+0x1b0/0x1b50
ra : 805ead08 __skb_get_hash_net+0x74/0x12c
Status: 11000403 KERNEL EXL IE
Cause : 40800010 (ExcCode 04)
BadVA : 85144817
PrId : 0001992f (MIPS 1004Kc)
Call Trace:
[<805e91f0>] __skb_flow_dissect+0x1b0/0x1b50
[<805ead08>] __skb_get_hash_net+0x74/0x12c
[<805ef330>] get_rps_cpu+0x1b8/0x3fc
[<805fca70>] netif_receive_skb_list_internal+0x324/0x364
[<805fd120>] napi_complete_done+0x68/0x2a4
[<8058de5c>] mtk_napi_rx+0x228/0xfec
[<805fd398>] __napi_poll+0x3c/0x1c4
[<805fd754>] napi_threaded_poll_loop+0x234/0x29c
[<805fd848>] napi_threaded_poll+0x8c/0xb0
[<80053544>] kthread+0x104/0x12c
[<80002bd8>] ret_from_kernel_thread+0x14/0x1c

Code: 02d51821 1060045b 00000000 <8c640000> 3084000f 2c820005 144001a2 00042080 8e220000

To reduce the attack surface and maintain performance, do not process
PPPoE PFC frames.

[1] https://lore.kernel.org/r/20220630231016.GA392@debian.home

Affected products

VendorProductAffectedFixed
Linux Linux 6.0 6.1.175

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 7.0.7-1 —
Debian 13 linux 6.12.88-1 —
Debian 12 linux 6.1.176-1 —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1028.33 —
Ubuntu 26.04 LTS linux 7.0.0-28.28 USN-8566-1
Ubuntu 26.04 LTS linux-aws +2 7.0.0-1009.9 USN-8618-1, USN-8603-1, USN-8568-1
Ubuntu 26.04 LTS linux-gcp +1 7.0.0-1008.8 USN-8593-1, USN-8566-1
Ubuntu 26.04 LTS linux-gke 7.0.0-1003.4 USN-8566-1
Ubuntu 26.04 LTS linux-ibm +1 7.0.0-1010.10 USN-8603-1, USN-8593-1
Ubuntu 26.04 LTS linux-nvidia 7.0.0-1016.16 USN-8663-1
Ubuntu 26.04 LTS linux-nvidia-bos 7.0.0-2016.16 USN-8664-1
Ubuntu 26.04 LTS linux-raspi 7.0.0-1015.15 USN-8618-1
Ubuntu 26.04 LTS linux-riscv +1 7.0.0-28.28.1 USN-8566-1
Ubuntu 25.10 linux +8 No fix yet —
Ubuntu 24.04 LTS linux 6.8.0-136.136 USN-8567-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1061.64 USN-8595-2
Ubuntu 24.04 LTS linux-azure 6.8.0-1063.71 USN-8606-1
Ubuntu 24.04 LTS linux-azure-7.0 7.0.0-1014.14~24.04.1 USN-8728-2
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1062.69 USN-8607-1
Ubuntu 24.04 LTS linux-azure-fde-7.0 7.0.0-1013.13~24.04.1 —
Ubuntu 24.04 LTS linux-gcp 6.8.0-1064.72 USN-8567-1
Ubuntu 24.04 LTS linux-gcp-7.0 +1 7.0.0-1011.11~24.04.1 USN-8728-3, USN-8728-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1059.67 USN-8567-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1046.50 USN-8567-1
Ubuntu 24.04 LTS linux-hwe-7.0 7.0.0-28.28~24.04.1 USN-8569-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1061.62 USN-8574-3
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-136.136.2 USN-8574-2
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1059.62 USN-8596-1
Ubuntu 24.04 LTS linux-nvidia-7.0 7.0.0-1016.16~24.04.1 USN-8663-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1059.62.1 USN-8596-1
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1030.31 USN-8574-3
Ubuntu 24.04 LTS linux-oracle 6.8.0-1058.61 USN-8574-2
Ubuntu 24.04 LTS linux-raspi 6.8.0-1061.65 USN-8665-1
Ubuntu 24.04 LTS linux-riscv +27 No fix yet —
Ubuntu 24.04 LTS linux-riscv-7.0 7.0.0-28.28.1~24.04.3 —
Ubuntu 24.04 LTS linux-vmware 6.8.0-1008.8 —
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1033.34 USN-8574-3
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1061.64~22.04.1 USN-8595-3
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1063.71~22.04.1 USN-8606-1
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1062.69~22.04.1 USN-8609-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1064.72~22.04.1 USN-8567-1
Ubuntu 22.04 LTS linux-hwe-6.8 6.8.0-136.136~22.04.1 USN-8619-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1061.62~22.04.1 USN-8574-3
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-136.136.2~22.04.1 USN-8574-2
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1059.62~22.04.1 USN-8596-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1058.61~22.04.1 USN-8595-1
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 22.04 LTS linux-riscv-6.8 6.8.0-136.136~22.04.3 —
Show 6 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 6.8.0-2050.52 USN-8665-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1056.57 USN-8567-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 +1 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1056.57~22.04.2 USN-8567-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1061.64+fips1 USN-8595-3
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1063.71+fips2 USN-8608-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-136.136+fips2 USN-8574-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1064.72+fips1 USN-8574-1
ReleasePackageFixed inAdvisory
RHEL 10 rv +76 6.12.0-211.52.1.el10_2 RHSA-2026:64775
RHEL 9 rv +75 5.14.0-687.46.1.el9_8 RHSA-2026:66180
RHEL 8 kernel-rt +12 4.18.0-553.164.1.rt7.505.el8_10 RHSA-2026:68532
RHEL 8 perf +26 4.18.0-553.164.1.el8_10 RHSA-2026:68531

AlmaLinux

Errata ↗
ReleasePackageFixed inAdvisory
AlmaLinux 9 rv +73 5.14.0-687.46.1.el9_8 ALSA-2026:66180
AlmaLinux 8 kernel-rt +9 4.18.0-553.164.1.rt7.505.el8_10 ALSA-2026:68532
AlmaLinux 8 perf +24 4.18.0-553.164.1.el8_10 ALSA-2026:68531

Rocky Linux

Errata ↗
ReleasePackageFixed inAdvisory
Rocky Linux 10 kernel 6.12.0-211.52.1.el10_2 RLSA-2026:64775
Rocky Linux 9 kernel 5.14.0-687.46.1.el9_8 RLSA-2026:66180
Rocky Linux 8 kernel 4.18.0-553.164.1.el8_10 RLSA-2026:68531
Rocky Linux 8 kernel-rt 4.18.0-553.164.1.rt7.505.el8_10 RLSA-2026:68532
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +7 6.4.0-150700.53.78.1 SUSE-SU-2026:3790-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.78.1.150700.17.43.2 SUSE-SU-2026:3790-1
Show 7 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.37.1 SUSE-SU-2026:23231-1, SUSE-SU-2026:23221-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.37.1.160000.2.19 SUSE-SU-2026:23231-1, SUSE-SU-2026:23221-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.37.1 SUSE-SU-2026:23237-1, SUSE-SU-2026:23231-1, SUSE-SU-2026:23221-1
SLES 16.0 kernel-default-base 6.12.0-160000.37.1.160000.2.19 SUSE-SU-2026:23231-1, SUSE-SU-2026:23221-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.37.1.160000.2.19 SUSE-SU-2026:23068-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.37.1 SUSE-SU-2026:23068-1, SUSE-SU-2026:23066-1
SLE Micro 6.1 kernel-rt +4 6.4.0-51.1 SUSE-SU-2026:23194-1, SUSE-SU-2026:23193-1
SLE Micro 6.0 kernel-rt +4 6.4.0-51.1 SUSE-SU-2026:23244-1, SUSE-SU-2026:23241-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.78.1 SUSE-SU-2026:3790-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_19 1-150700.1.5.1 SUSE-SU-2026:3810-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_20 1-150700.15.3.2 SUSE-SU-2026:3790-1
SUSE Real Time Module 15 SP7 kernel-rt +2 6.4.0-150700.7.72.1 SUSE-SU-2026:3810-1
ReleasePackageFixed inAdvisory
openSUSE Tumbleweed kernel-source 7.0.12-1.1 openSUSE-SU-2026:11014-1
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.37.1.160000.2.19 openSUSE-SU-2026:21555-1
openSUSE Leap 16.0 kernel-rt +11 6.12.0-160000.37.1 openSUSE-SU-2026:21555-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.18.30-61.116 +2 1:1.0-0.amzn2023 ALAS2023-2026-1882, ALAS2023-2026-1754, ALAS2023-2026-1753
Amazon Linux 2023 perf +11 1:6.1.175-219.357.amzn2023 ALAS2023-2026-1882
Amazon Linux 2023 perf6.12 +11 1:6.12.88-119.157.amzn2023 ALAS2023-2026-1753
Amazon Linux 2023 perf6.18 +11 1:6.18.30-61.116.amzn2023 ALAS2023-2026-1754

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.141.1-1 —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 8 perf +19 4.18.0-553.164.1.el8_10 ELSA-2026-68531

Advisories 50

References