Description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked()
Commit 96c4af418586 ("cifs: Fix locking usage for tcon fields")
refactored cifs code to change cifs_tcp_ses_lock for tc_lock around
tc_count changes.
There was missing lock around tc_count increment inside
smb2_find_smb_sess_tcon_unlocked().
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.6.128 – < 6.6.142, 6.12.75 – < 6.12.92, 6.18.16 – < 6.18.34, 6.19.6 – < 6.20, 7.0 | 6.6.142 |
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 | 7.0.12-1 | — |
| Debian 13 | linux | 6.12.94-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1030.35 | — |
| Ubuntu 26.04 LTS | linux | 7.0.0-28.28 | — |
| Ubuntu 26.04 LTS | linux-aws +2 | 7.0.0-1009.9 | USN-8618-1, USN-8603-1 |
| Ubuntu 26.04 LTS | linux-gcp +1 | 7.0.0-1008.8 | USN-8593-1 |
| Ubuntu 26.04 LTS | linux-gke | 7.0.0-1003.4 | — |
| 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 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-139.139 | USN-8729-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1064.67 | USN-8729-6 |
| 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 | 6.8.0-1065.72 | — |
| Ubuntu 24.04 LTS | linux-azure-fde-7.0 | 7.0.0-1013.13~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-gcp +1 | 6.8.0-1067.75 | USN-8761-1, USN-8729-1 |
| 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 | 6.8.0-1062.70 | USN-8729-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1049.53 | USN-8729-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-28.28~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1064.65 | USN-8729-3 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-139.139.1 | USN-8729-4 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1062.65 | USN-8729-1 |
| 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 | 6.8.0-1062.65.1 | USN-8729-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1035.38 | USN-8781-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1061.64 | USN-8802-1 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1064.68 | USN-8729-1 |
| Ubuntu 24.04 LTS | linux-riscv +22 | 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 | 6.8.0-1036.37 | USN-8729-3 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1064.67~22.04.1 | USN-8729-6 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1065.72~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 +1 | 6.8.0-1067.75~22.04.1 | USN-8761-3, USN-8729-3 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-149.149~22.04.1 | USN-9066-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1066.67~22.04.1 | USN-8906-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-139.139.1~22.04.1 | USN-8729-4 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1062.65~22.04.1 | USN-8729-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1061.64~22.04.1 | USN-8802-1 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-139.139~22.04.1 | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 | 6.8.0-2053.55 | USN-8729-2 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1059.60 | USN-8729-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1059.60~22.04.1 | USN-8729-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1064.67+fips1 | USN-8729-5 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-139.139+fips1 | USN-8729-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips +1 | 6.8.0-1067.75+fips1 | USN-8761-2, USN-8729-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | rv +76 | 6.12.0-211.50.1.el10_2 | RHSA-2026:61887 |
| RHEL 9 | rv +75 | 5.14.0-687.45.1.el9_8 | RHSA-2026:64808 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | rv +74 | 6.12.0-211.50.1.el10_2 | ALSA-2026:61887 |
| AlmaLinux 9 | rv +73 | 5.14.0-687.45.1.el9_8 | ALSA-2026:64808 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | kernel | 6.12.0-211.50.1.el10_2 | RLSA-2026:61887 |
| Rocky Linux 9 | kernel | 5.14.0-687.45.1.el9_8 | RLSA-2026:64808 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +7 | 6.4.0-150700.53.81.1 | SUSE-SU-2026:4254-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.81.1.150700.17.45.1 | SUSE-SU-2026:4254-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.81.1 | SUSE-SU-2026:4254-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_20 | 1-150700.1.3.1 | SUSE-SU-2026:4120-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_21 | 1-150700.15.3.1 | SUSE-SU-2026:4254-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.75.1 | SUSE-SU-2026:4120-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.35-68.127 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-1894, ALAS2023-2026-1881 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.92-122.166.amzn2023 | ALAS2023-2026-1894 |
| Amazon Linux 2023 | perf6.18 +12 | 1:6.18.35-68.127.amzn2023 | ALAS2023-2026-1881 |
Advisories 32
- USN-9066-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · 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
- WID-SEC-2026-2403 Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Nov 11, 2026
- USN-8729-1 linux, linux-fips, linux-gcp, linux-gcp-fips, linux-gke, linux-gkeop, linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency, linux-raspi, linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8906-1 linux-ibm-6.8 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-8761-3 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8729-6 linux-aws, linux-aws-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8781-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8729-4 linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8618-1 linux-aws, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8802-1 linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8729-5 linux-aws-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8729-3 linux-gcp-6.8, linux-ibm, linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8729-2 linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8761-2 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8761-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- ALSA-2026:64808 Important: kernel security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:61887 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2026:61887 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:64808 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- SUSE-SU-2026:4254-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 8, 2026
- SUSE-SU-2026:4120-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Sep 14, 2026
- RLSA-2026:64808 Important: kernel security update Rocky Linux Security Advisories · Sep 9, 2026
- RLSA-2026:61887 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 2, 2026
- ALAS2023-2026-1881 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 12, 2026
- ALAS2023-2026-1894 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 6, 2026
References
- https://git.kernel.org/stable/c/7585d4242f59185b084957fa077396e53dbf7c24
- https://git.kernel.org/stable/c/7df1df6f40c0720d30206aa35c0343b962350e0d
- https://git.kernel.org/stable/c/13fb413ae22a37c69341918a6d651d19a9b0b9b7
- https://git.kernel.org/stable/c/bf4ebdb19ff9b3cdf992b50715fe61633327416a
- https://git.kernel.org/stable/c/e374f4e496fef8168784f93a4477d67be34485fd
- https://git.kernel.org/stable/c/4d8690dace005a38e6dbde9ecce2da3ad85c7c41