Description
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix uninitialized local_id in syncookie MP_JOIN reconstruction
mptcp_token_join_cookie_init_state() restores remote_nonce, local_nonce,
backup, join_id, token and msk from the saved cookie entry when rebuilding
the request socket for a MP_JOIN 4th-ACK handled under SYN cookies, but it
does not restore local_id, even though the SYN path saved it.
subflow_ulp_clone() then reads that uninitialized field and stores it as
the joined subflow's address-ID. Because the request-sock slab is
SLAB_TYPESAFE_BY_RCU and not zeroed on allocation, the value is the stale
byte of a previously freed request socket, which an off-path peer can
influence by sending concurrent MP_JOIN SYNs. This corrupts the path
manager's id-based subflow bookkeeping for the connection.
Restore subflow_req->local_id from the cookie entry, as done for the other
fields.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.9 | 5.10.270 |
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 | 7.2.6-1 | — |
| Debian 13 | linux | 6.12.111-1 | — |
| Debian 12 | linux | 6.1.190-1 | — |
| Debian 12 | linux-6.12 | 6.12.111-1~deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1036.41 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1103.105 | — |
| Ubuntu 26.04 LTS | linux | 7.0.0-42.42 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-aws | 7.0.0-1016.17 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-azure | 7.0.0-1020.21 | USN-9019-1 |
| Ubuntu 26.04 LTS | linux-azure-fde | 7.0.0-1019.19 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-gcp | 7.0.0-1016.18 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-gke | 7.0.0-1010.11 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1017.17 | USN-8960-1, USN-8959-1 |
| Ubuntu 26.04 LTS | linux-nvidia +1 | No fix yet | — |
| Ubuntu 26.04 LTS | linux-oracle | 7.0.0-1015.16 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1023.23 | USN-9021-1 |
| Ubuntu 26.04 LTS | linux-realtime | 7.0.0-43.43.1 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-riscv | 7.0.0-42.42.1 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-149.149 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1069.74 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-aws-7.0 | 7.0.0-1017.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1073.82 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1071.78 | USN-9039-1 |
| Ubuntu 24.04 LTS | linux-azure-fde-7.0 | 7.0.0-1019.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1073.81 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-gcp-7.0 | 7.0.0-1017.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1068.77 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1053.57 | USN-9023-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | USN-8959-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1069.70 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-149.149.1 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1067.70 | USN-9024-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1067.70.1 | USN-9040-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1038.42 | USN-9002-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1067.71 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-oracle-7.0 | 7.0.0-1016.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1068.72 | USN-9025-1 |
| Ubuntu 24.04 LTS | linux-riscv +31 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-vmware | 6.8.0-1010.10 | USN-9022-1 |
| Ubuntu 22.04 LTS | linux | 5.15.0-202.212 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1119.126 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1069.74~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1125.134 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1073.82~22.04.1 | USN-9026-1 |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1124.133 | USN-8962-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1071.78~22.04.1 | USN-9026-1 |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1120.130 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1073.81~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-gke | 5.15.0-1115.121 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1102.110 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-ibm | 5.15.0-1113.117 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1069.70~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1114.120 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-kvm | 5.15.0-1111.116 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-lowlatency | 5.15.0-197.207 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-149.149.1~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1114.115 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1070.72 | USN-8963-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1059.59 | USN-8963-1 |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1116.122 | USN-8961-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1067.71~22.04.1 | USN-9025-1 |
| Ubuntu 22.04 LTS | linux-raspi | 5.15.0-1113.116 | USN-9029-1 |
| Ubuntu 22.04 LTS | linux-riscv +35 | No fix yet | — |
Show 9 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 | 6.8.0-2056.58 | USN-9025-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1064.65 | USN-9023-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1111.115 | USN-8961-1 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1118.127 | USN-8961-1 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1064.65~22.04.1 | USN-9024-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1069.74+fips1 | USN-9023-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1073.82+fips1 | USN-9022-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1073.81+fips1 | USN-9023-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-aws-fips | 5.15.0-1119.126+fips1 | USN-8961-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-azure-fips | 5.15.0-1125.134+fips1 | USN-8961-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips | 5.15.0-202.212+fips1 | USN-8961-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-gcp-fips | 5.15.0-1120.130+fips1 | USN-8961-1 |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux-aws-5.15 | 5.15.0-1119.126~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-azure-5.15 | 5.15.0-1125.134~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-azure-fde-5.15 | 5.15.0-1124.133~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-gcp-5.15 | 5.15.0-1120.130~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-hwe-5.15 | 5.15.0-202.212~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-ibm-5.15 | 5.15.0-1113.117~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1114.120~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-lowlatency-hwe-5.15 | 5.15.0-197.207~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1070.72~20.04.1 | USN-8963-1 |
| Ubuntu Pro 20.04 LTS | linux-oracle-5.15 | 5.15.0-1116.122~20.04.1 | USN-8961-1 |
| Ubuntu Pro 20.04 LTS | linux-riscv-5.15 | 5.15.0-1113.117~20.04.2 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.41.1 | SUSE-SU-2026:24662-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.41.1.160000.2.32 | SUSE-SU-2026:24662-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.41.1 | SUSE-SU-2026:24662-1, SUSE-SU-2026:24651-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.41.1.160000.2.32 | SUSE-SU-2026:24662-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.41.1.160000.2.32 | SUSE-SU-2026:24643-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.41.1 | SUSE-SU-2026:24648-1, SUSE-SU-2026:24643-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-159998.55.1.159998.21.41 | SUSE-SU-2026:24619-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-159998.55.1 | SUSE-SU-2026:24619-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-159998.55.1.159998.21.42 | SUSE-SU-2026:24550-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-159998.55.1 | SUSE-SU-2026:24550-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.2.7-1.1 | openSUSE-SU-2026:11880-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.1.188-233.385 +2 | 1:1.0-0.amzn2023 | ALAS2023-2026-3197, ALAS2023-2026-3196, ALAS2023-2026-3187 |
| Amazon Linux 2023 | perf +11 | 1:6.1.188-233.385.amzn2023 | ALAS2023-2026-3197 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.110-135.201.amzn2023 | ALAS2023-2026-3196 |
| Amazon Linux 2023 | perf6.18 +12 | 1:6.18.51-120.162.amzn2023 | ALAS2023-2026-3187 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.157.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-207.111.5.1.el10uek | ELSA-2026-500374 |
Advisories 29
- USN-9040-1 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9039-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8961-1 linux, linux-aws, linux-aws-5.15, linux-aws-fips, linux-azure, linux-azure-5.15, linux-azure-fde-5.15, linux-azure-fips, linux-fips, linux-gcp, linux-gcp-5.15, linux-gcp-fips, linux-gke, linux-gkeop, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, linux-intel-iot-realtime, linux-intel-iotg, linux-intel-iotg-5.15, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux-oracle, linux-oracle-5.15, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9022-1 linux, linux-aws, linux-azure, linux-azure-fips, linux-gcp, linux-gke, linux-ibm, linux-lowlatency, linux-oracle, linux-vmware vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9020-1 linux-aws-7.0, linux-azure-fde, linux-azure-fde-7.0, linux-gcp-7.0, linux-gke, linux-oracle-7.0, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9024-1 linux-aws-6.8, linux-gcp-6.8, linux-ibm-6.8, linux-lowlatency-hwe-6.8, linux-nvidia, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8959-1 linux, linux-aws, linux-gcp, linux-hwe-7.0, linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8963-1 linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9025-1 linux-oracle-6.8, linux-raspi, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- SUSE-SU-2026:24662-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 12, 2026
- SUSE-SU-2026:24651-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 12, 2026
- SUSE-SU-2026:24643-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 12, 2026
- SUSE-SU-2026:24648-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 12, 2026
- SUSE-SU-2026:24619-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 12, 2026
- USN-9019-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- USN-9029-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- USN-9023-1 linux-aws-fips, linux-gcp-fips, linux-gkeop, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- USN-9026-1 linux-azure-6.8, linux-azure-fde-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- USN-9021-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- WID-SEC-2026-3321 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 10, 2026
- USN-8960-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-9002-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8962-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- SUSE-SU-2026:24550-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 6, 2026
- ALAS2023-2026-3196 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 21, 2026
- ALAS2023-2026-3197 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 21, 2026
- ALAS2023-2026-3187 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 12, 2026
- ELSA-2026-500374 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 7, 2026
- openSUSE-SU-2026:11880-1 kernel-devel-7.2.7-1.1 on GA media SUSE / openSUSE Security Updates · Sep 25, 2026
References
- https://git.kernel.org/stable/c/4534e0eead692bb069ad1e6a5a245fc2e2078300
- https://git.kernel.org/stable/c/63cacb05e51a1c6e1349d2e593d00fd6ef43def4
- https://git.kernel.org/stable/c/954b5ea836eb118d188975ced803448537ab8479
- https://git.kernel.org/stable/c/9df36a4846375a9b75bf42d77bfed216b0f366f9
- https://git.kernel.org/stable/c/64f2c5dd49b956a542c8c02b8dad5d262a462bba
- https://git.kernel.org/stable/c/51887ccd88791ddaa8755a7c614fda031ecf7982
- https://git.kernel.org/stable/c/bf19d166337c6488b39cb03eeeffb30a941d6326
- https://git.kernel.org/stable/c/b878dfdd12d7a5b8722a78d35e313506140ca3d9