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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| 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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 7.0.7-1 | — |
| Debian 13 | linux | 6.12.88-1 | — |
| Debian 12 | linux | 6.1.176-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.141.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-553.164.1.el8_10 | ELSA-2026-68531 |
Advisories 50
- WID-SEC-2026-1827 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8728-1 linux-gcp-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8728-2 linux-azure-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8728-3 linux-oracle-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- SSA-457936 SSA-457936: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.7 Siemens ProductCERT · Nov 10, 2026
- USN-8574-3 linux-ibm, linux-ibm-6.8, linux-nvidia-tegra, linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-3 linux-aws-6.8, linux-aws-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8574-2 linux-fips, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8596-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8665-1 linux-raspi, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8593-1 linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8664-1 linux-nvidia-bos vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8603-1 linux-azure, linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8663-1 linux-nvidia, linux-nvidia-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8608-1 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8618-1 linux-aws, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8574-1 linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-2 linux-aws vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-1 linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8567-1 linux, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8606-1 linux-azure, linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8607-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8619-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8566-1 linux, linux-gcp, linux-gke, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8569-1 linux-hwe-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8609-1 linux-azure-fde-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8568-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- ALSA-2026:66180 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:68531 Important: kernel security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:68532 Important: kernel-rt security update AlmaLinux Security Advisories · Oct 29, 2026
- ICSA-26-295-16 Siemens SIMATIC S7-1500 TM MFP CISA ICS & IT advisories · Oct 22, 2026
- ICSA-26-295-11 Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP CISA ICS & IT advisories · Oct 22, 2026
- RHSA-2026:66180 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- WID-SEC-2026-3891 Siemens SIMATIC S7: Mehrere Schwachstelle BSI CERT-Bund (WID) · Oct 18, 2026
- RHSA-2026:64775 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- RHSA-2026:68532 Red Hat Security Advisory: kernel-rt security update Red Hat Security Advisories (RHSA) · Oct 16, 2026
- RHSA-2026:68531 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- SSA-784472 SSA-784472: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1.1 Siemens ProductCERT · Oct 13, 2026
- SSA-019113 SSA-019113: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.6 Siemens ProductCERT · Oct 13, 2026
- RLSA-2026:68531 Important: kernel security update Rocky Linux Security Advisories · Sep 19, 2026
- RLSA-2026:68532 Important: kernel-rt security update Rocky Linux Security Advisories · Sep 19, 2026
- ELSA-2026-68531 Important: kernel security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Sep 18, 2026
- RLSA-2026:66180 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 11, 2026
- RLSA-2026:64775 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 9, 2026
- SUSE-SU-2026:3810-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 31, 2026
- SUSE-SU-2026:23244-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:23231-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:23237-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:23241-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:23221-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 27, 2026
References
- https://git.kernel.org/stable/c/e7c811ca372d53c2be7d01a1614e71fae1054836
- https://git.kernel.org/stable/c/abc5bc84e0f2edc7ea2d437afa6ef3fe1fc43200
- https://git.kernel.org/stable/c/18ae9eacfc95cc715c0606b2c86e8aa8a86cf3e3
- https://git.kernel.org/stable/c/db104b0d8a7856397c0469d83a4289adf7c54863
- https://git.kernel.org/stable/c/6044392d9cace3a3672b02c8bc7d38b502e51734
- https://git.kernel.org/stable/c/0d00b9015069712944934bab09eaa6c542143049
- https://git.kernel.org/stable/c/7c93f353eab4ea911e394630f07d72e040a729d8
- https://git.kernel.org/stable/c/d6c19b31a3c1d519fabdcf0aa239e6b6109b9473