Vulnerability · Published Mar 25, 2026 · Assigned by Linux
CVE-2026-23364ksmbd: Compare MACs in constant time
High 7.4
In plain English
A high-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 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.4High
Exploit odds (30 days)0.4%top 63.8% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: Compare MACs in constant time To prevent timing attacks, MAC comparisons need to be constant-time. Replace the memcmp() with the correct function, crypto_memneq().
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.170-1 | DEBIAN-CVE-2026-23364 |
| Debian:13 | linux | 6.12.85-1 | DEBIAN-CVE-2026-23364 |
| Debian:14 | linux | 6.19.8-1 | DEBIAN-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux | 5.15.0-198.208 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux | 5.15.0-198.208 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux | 6.8.0-136.136 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1117.124 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1117.124 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1061.64 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-aws | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1061.64~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1123.132 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1123.132 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1063.71 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-azure | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | 6.8.0-1063.71~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1122.131 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1122.131 | USN-8876-1 |
| Ubuntu:24.04:LTS | linux-azure-fde | 6.8.0-1062.69 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | 6.8.0-1062.69~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1118.128 | USN-8877-1 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1118.128 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1064.72 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-gcp | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | 6.8.0-1064.72~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1113.119 | USN-8875-1 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1113.119 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1059.67 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1100.108 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1100.108 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1046.50 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | 6.8.0-136.136~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1111.115 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1111.115 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1061.62 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1061.62~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1112.118 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1112.118 | USN-8875-1 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1109.114 | USN-8875-1 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1109.114 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-195.205 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-195.205 | USN-8875-1 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-136.136.2 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | 6.8.0-136.136.2~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1112.113 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1112.113 | USN-8875-2 |
| Ubuntu:24.04:LTS | linux-nvidia | 6.8.0-1059.62 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1059.62~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | 6.8.0-1059.62.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1070.72 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1030.31 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1059.59 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1114.120 | USN-8875-1 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1114.120 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1058.61 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-oracle | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | 6.8.0-1058.61~22.04.1 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1061.65 | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-raspi | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-realtime | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:25.10 | linux-riscv | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | 6.8.0-136.136~22.04.3 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-vmware | 6.8.0-1008.8 | UBUNTU-CVE-2026-23364 |
| Ubuntu:24.04:LTS | linux-xilinx | 6.8.0-1033.34 | UBUNTU-CVE-2026-23364 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1080.84 | USN-8875-1 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1080.84 | UBUNTU-CVE-2026-23364 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 8a665d733940592e671ec6afadcd0be80a091a80e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before cd52a0e309659537048a864211abc3ea4c5caa63e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 307afccb751f542246bd5dc68a2c1ffe1a78418ce2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 2cdc56ed67615ba0921383a688f24415ebe065f3e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 93c0a22fec914ec4b697e464895a0f594e29fb28e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before f4588b85efd6007d46b80aa1b9fb746628ffb3dce2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before c5794709bc9105935dbedef8b9cf9c06f2b559fa |
| Linux | Linux | 5.15 |
References
- https://git.kernel.org/stable/c/8a665d733940592e671ec6afadcd0be80a091a80
- https://git.kernel.org/stable/c/cd52a0e309659537048a864211abc3ea4c5caa63
- https://git.kernel.org/stable/c/307afccb751f542246bd5dc68a2c1ffe1a78418c
- https://git.kernel.org/stable/c/2cdc56ed67615ba0921383a688f24415ebe065f3
- https://git.kernel.org/stable/c/93c0a22fec914ec4b697e464895a0f594e29fb28
- https://git.kernel.org/stable/c/f4588b85efd6007d46b80aa1b9fb746628ffb3dc
- https://git.kernel.org/stable/c/c5794709bc9105935dbedef8b9cf9c06f2b559fa
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html