Description
An issue was discovered in the Linux kernel before 6.3.8. fs/smb/server/connection.c in ksmbd does not validate the relationship between the NetBIOS header's length field and the SMB header sizes, via pdu_size in ksmbd_conn_handler_loop, leading to an out-of-bounds read.
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 | 6.3.11-1 | — |
| Debian 13 | linux | 6.3.11-1 | — |
| Debian 12 | linux | 6.1.37-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1040.42 | — |
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux +1 | 5.15.0-102.112 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1057.63 | USN-6725-2 |
| Ubuntu 22.04 LTS | linux-aws-6.2 | 6.2.0-1013.13~22.04.1 | USN-6412-1 |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1060.69 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-azure-6.2 +1 | 6.2.0-1014.14~22.04.1 | USN-6412-1 |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1060.69.1 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.2 | 6.2.0-1014.14~22.04.1.1 | USN-6412-1 |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1055.63 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.2 | 6.2.0-1016.18~22.04.1 | USN-6412-1 |
| Ubuntu 22.04 LTS | linux-gke +1 | 5.15.0-1054.59 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1040.46 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.2 | 6.2.0-34.34~22.04.1 | USN-6412-1 |
| Ubuntu 22.04 LTS | linux-ibm +1 | 5.15.0-1050.53 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1052.58 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1048.48 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.2 | 6.2.0-1011.11 | USN-6466-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1025.25 | — |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1012.12 | — |
| Ubuntu 22.04 LTS | linux-oem-6.1 | 6.1.0-1016.16 | — |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1055.61 | USN-6725-1 |
| Ubuntu 22.04 LTS | linux-riscv +12 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-xilinx-zynqmp | 5.15.0-1030.34 | — |
| Ubuntu 20.04 LTS | linux-aws-5.15 | 5.15.0-1057.63~20.04.1 | USN-6725-2 |
| Ubuntu 20.04 LTS | linux-azure-5.15 | 5.15.0-1060.69~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-azure-fde-5.15 | 5.15.0-1060.69~20.04.1.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-gcp-5.15 | 5.15.0-1055.63~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-gkeop-5.15 | 5.15.0-1040.46~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-hwe-5.15 +1 | 5.15.0-102.112~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-ibm-5.15 | 5.15.0-1050.53~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1052.58~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1025.25~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-oracle-5.15 | 5.15.0-1055.61~20.04.1 | USN-6725-1 |
| Ubuntu 20.04 LTS | linux-riscv +24 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-riscv-5.15 | 5.15.0-1053.57~20.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp +13 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1050.52 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1058.66 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-aws-fips | 5.15.0-1057.63+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-azure-fips | 5.15.0-1060.69+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips | 5.15.0-102.112+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-gcp-fips | 5.15.0-1055.63+fips2 | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | kernel | 5.15.122.1-2 | — |
Advisories 5
- USN-6725-1 linux, linux-azure, linux-azure-5.15, linux-azure-fde, linux-azure-fde-5.15, linux-gcp, linux-gcp-5.15, linux-gke, linux-gkeop, linux-gkeop-5.15, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, 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-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-6725-2 linux-aws, linux-aws-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-6466-1 linux-nvidia-6.2 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-6412-1 linux, linux-aws, linux-aws-6.2, linux-azure, linux-azure-6.2, linux-azure-fde-6.2, linux-gcp, linux-gcp-6.2, linux-hwe-6.2, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-6.2, linux-oracle, linux-raspi, linux-starfive vulnerabilities Ubuntu Security Notices (USN) · Oct 23, 2026
- WID-SEC-2023-1770 Linux Kernel: Mehrere Schwachstellen ermöglichen Offenlegung von Informationen oder Umgehung von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Apr 16, 2024