Vulnerability · Published Jul 25, 2026 · Assigned by Linux
CVE-2026-64392ksmbd: use opener credentials for delete-on-close
Critical 9.1
In plain English
A critical-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for delete-on-close Delete-on-close can be completed by deferred or durable handle teardown, where no request work is available. Both the base-file unlink and the ADS xattr removal consequently run with the ksmbd worker credentials and can bypass filesystem permission checks. Run both operations with the credentials captured in struct file when the handle was opened. This preserves the authenticated user's fsuid, fsgid, supplementary groups and capability restrictions at final close.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | no fix listed | DEBIAN-CVE-2026-64392 |
| Debian:13 | linux | 6.12.96-1 | DEBIAN-CVE-2026-64392 |
| Debian:14 | linux | 7.1.4-1 | DEBIAN-CVE-2026-64392 |
| Debian:12 | linux-6.12 | 6.12.100-1~deb12u1 | DEBIAN-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux | 6.8.0-147.147 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux | 7.0.0-31.31 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-aws | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1067.70 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-aws | 7.0.0-1012.12 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-aws-7.0 | 7.0.0-1012.12~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1071.79 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-azure | 7.0.0-1014.14 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-7.0 | 7.0.0-1014.14~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-fde | 6.8.0-1069.76 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-azure-fde | 7.0.0-1013.13 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-fde-7.0 | 7.0.0-1013.13~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gcp | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1071.79 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-gcp | 7.0.0-1011.11 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gcp-7.0 | 7.0.0-1011.11~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1066.74 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-gke | 7.0.0-1006.7 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-gkeop | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1052.56 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-hwe-7.0 | 7.0.0-31.31~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-ibm | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1067.68 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-ibm | 7.0.0-1013.13 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-intel-iotg | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-kvm | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-lowlatency | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-147.147.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-nvidia | 7.0.0-1018.18 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia-7.0 | 7.0.0-1018.18~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-nvidia-bos | 7.0.0-2018.18 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1035.38 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-oem-7.0 | 7.0.0-1013.13 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oracle | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1064.67 | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-oracle | 7.0.0-1011.11 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-oracle-7.0 | 7.0.0-1011.11~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-raspi | 7.0.0-1019.19 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-realtime | 7.0.0-31.31.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:26.04:LTS | linux-riscv | 7.0.0-31.31.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-riscv-7.0 | 7.0.0-31.31.1~24.04.1 | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-vmware | 6.8.0-1008.8 | UBUNTU-CVE-2026-64392 |
| Ubuntu:24.04:LTS | linux-xilinx | no fix listed | UBUNTU-CVE-2026-64392 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | no fix listed | UBUNTU-CVE-2026-64392 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | f44158485826c076335d6860d35872271a83791d – before 3cb2e6e2a6798909507b9d695e4b80e685e72d26f44158485826c076335d6860d35872271a83791d – before f08b3f451f12eee4abd8a5981803bc36db84458bf44158485826c076335d6860d35872271a83791d – before 18c59109bb6fb816d5102171666f87cf1e29901df44158485826c076335d6860d35872271a83791d – before e72c15085b6d86f45d224d98aa75b5cace4aaab9f44158485826c076335d6860d35872271a83791d – before 4b7059974549d278e30fe70e2a4e421f9839817df44158485826c076335d6860d35872271a83791d – before 52e2f21911158ec961cd5aae19c56460db382af0 |
| Linux | Linux | 5.15 |
References
- https://git.kernel.org/stable/c/3cb2e6e2a6798909507b9d695e4b80e685e72d26
- https://git.kernel.org/stable/c/f08b3f451f12eee4abd8a5981803bc36db84458b
- https://git.kernel.org/stable/c/18c59109bb6fb816d5102171666f87cf1e29901d
- https://git.kernel.org/stable/c/e72c15085b6d86f45d224d98aa75b5cace4aaab9
- https://git.kernel.org/stable/c/4b7059974549d278e30fe70e2a4e421f9839817d
- https://git.kernel.org/stable/c/52e2f21911158ec961cd5aae19c56460db382af0