Description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix off-by-8 bounds check in check_wsl_eas()
The bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA
name and value, but ea_data sits at offset sizeof(struct
smb2_file_full_ea_info) = 8 from ea, not at offset 0. The strncmp()
later reads ea->ea_data[0..nlen-1] and the value bytes follow at
ea_data[nlen+1..nlen+vlen], so the actual end is ea->ea_data + nlen + 1
+ vlen. Isn't pointer math fun?
The earlier check (u8 *)ea > end - sizeof(*ea) only guarantees the
8-byte header is in bounds, but since the last EA is placed within 8
bytes of the end of the response, the name and value bytes are read past
the end of iov.
Fix this mess all up by using ea->ea_data as the base for the bounds
check.
An "untrusted" server can use this to leak up to 8 bytes of kernel heap
into the EA name comparison and influence which WSL xattr the data is
interpreted as.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.6.32 – < 6.6.136, 6.9 | 6.6.136 |
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 | 6.19.14-1 | — |
| Debian 13 | linux | 6.12.85-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | linux | 7.0.0-27.27 | USN-8488-1 |
| Ubuntu 26.04 LTS | linux-aws | 7.0.0-1008.8 | USN-8488-1 |
| Ubuntu 26.04 LTS | linux-azure | 7.0.0-1010.10 | USN-8603-1 |
| Ubuntu 26.04 LTS | linux-gcp +1 | 7.0.0-1007.7 | USN-8488-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1009.9 | USN-8603-1, USN-8488-1 |
| Ubuntu 26.04 LTS | linux-nvidia | 7.0.0-1013.13 | USN-8507-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1014.14 | USN-8488-2 |
| Ubuntu 26.04 LTS | linux-riscv +1 | 7.0.0-27.27.1 | USN-8488-1 |
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-28.28~24.04.1 | USN-8569-1 |
| Ubuntu 24.04 LTS | linux-riscv +27 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 3 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-realtime-6.14 +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.60.1 | SUSE-SU-2026:2482-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.60.1.150700.17.35.4 | SUSE-SU-2026:2482-1 |
| SLES 15 SP7 | kernel-obs-build | 6.4.0-150700.53.60.2 | SUSE-SU-2026:2482-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.115.1 | SUSE-SU-2026:2310-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.115.1.150600.12.54.1 | SUSE-SU-2026:2310-1 |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.34.1 | SUSE-SU-2026:22087-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.34.1.160000.2.15 | SUSE-SU-2026:22087-1 |
| SLES for SAP 15 SP6 | kernel-default-base | 6.4.0-150600.23.115.1.150600.12.54.1 | SUSE-SU-2026:2310-1 |
| SLES for SAP 15 SP6 | kernel-docs +4 | 6.4.0-150600.23.115.1 | SUSE-SU-2026:2310-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.34.1 | SUSE-SU-2026:22087-1, SUSE-SU-2026:22076-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.34.1.160000.2.15 | SUSE-SU-2026:22087-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.34.1.160000.2.15 | SUSE-SU-2026:22048-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.34.1 | SUSE-SU-2026:22048-1, SUSE-SU-2026:22043-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-47.1.21.24 | SUSE-SU-2026:22137-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-48.1 | SUSE-SU-2026:22458-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-47.1 | SUSE-SU-2026:22137-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-47.1.21.24 | SUSE-SU-2026:22108-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-48.1 | SUSE-SU-2026:22433-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-47.1 | SUSE-SU-2026:22108-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.60.1 | SUSE-SU-2026:2482-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_16 | 1-150700.1.5.2 | SUSE-SU-2026:2591-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_16 | 1-150700.15.3.2 | SUSE-SU-2026:2482-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.115.1 | SUSE-SU-2026:2310-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_27 | 1-150600.13.3.1 | SUSE-SU-2026:2310-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +1 | 6.4.0-150700.7.59.2 | SUSE-SU-2026:2591-1 |
| SUSE Real Time Module 15 SP7 | kernel-syms-rt | 6.4.0-150700.7.59.1 | SUSE-SU-2026:2591-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.0.3-1.1 | openSUSE-SU-2026:10703-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.25-55.108 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-1695, ALAS2023-2026-1693 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.83-113.160.amzn2023 | ALAS2023-2026-1695 |
| Amazon Linux 2023 | perf6.18 +11 | 1:6.18.25-55.108.amzn2023 | ALAS2023-2026-1693 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.137.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-204.92.4.2.el10uek | ELSA-2026-50372 |
Advisories 21
- USN-8603-1 linux-azure, linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- WID-SEC-2026-1279 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8488-1 linux, linux-aws, linux-gcp, linux-ibm, linux-oracle, 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-8488-2 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8507-1 linux-nvidia vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- SUSE-SU-2026:22043-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:22458-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 4, 2026
- SUSE-SU-2026:22433-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 3, 2026
- ELSA-2026-50372 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 2, 2026
- SUSE-SU-2026:2591-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 24, 2026
- SUSE-SU-2026:2482-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 24, 2026
- SUSE-SU-2026:22137-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 18, 2026
- SUSE-SU-2026:22108-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 17, 2026
- SUSE-SU-2026:22087-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 16, 2026
- SUSE-SU-2026:22076-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 16, 2026
- SUSE-SU-2026:22048-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 10, 2026
- SUSE-SU-2026:2310-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jun 10, 2026
- ALAS2023-2026-1693 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · May 19, 2026
- ALAS2023-2026-1695 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · May 19, 2026
- openSUSE-SU-2026:10703-1 kernel-devel-7.0.3-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2026
References
- https://git.kernel.org/stable/c/bfbc74df8bbe095b3ed68f6d4487b368af087890
- https://git.kernel.org/stable/c/5cc0574c84aa73946ade587c41e81757b8b01cb5
- https://git.kernel.org/stable/c/b2b76d09a64c538c57006180103fc1841e8cfa66
- https://git.kernel.org/stable/c/ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18
- https://git.kernel.org/stable/c/a893f1757d9a4009e4a8d7ceb2312142fe29cea4
- https://git.kernel.org/stable/c/3d8b9d06bd3ac4c6846f5498800b0f5f8062e53b