Log in Start free

Vulnerability · Published Jul 19, 2026 · Assigned by Linux

CVE-2026-64138ksmbd: validate SID in parent security descriptor during ACL inheritance

High 8.8

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 39% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.4%top 60.9% 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: validate SID in parent security descriptor during ACL inheritance Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved from the parent directory.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linuxno fix listedDEBIAN-CVE-2026-64138
Debian:13linux6.12.94-1DEBIAN-CVE-2026-64138
Debian:14linux7.0.12-1DEBIAN-CVE-2026-64138
Ubuntu:22.04:LTSlinuxno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux6.8.0-139.139UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux7.0.0-28.28UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-aws6.8.0-1064.67UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-aws7.0.0-1009.9UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1064.67~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure6.8.0-1067.75UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-azure7.0.0-1010.10UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1067.75~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-7.07.0.0-1014.14~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-fde6.8.0-1065.72UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-azure-fde7.0.0-1009.9UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-azure-fde-6.86.8.0-1065.72~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-fde-7.07.0.0-1013.13~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gcp6.8.0-1067.75UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-gcp7.0.0-1008.8UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1067.75~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gcp-7.07.0.0-1011.11~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gke6.8.0-1062.70UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-gke7.0.0-1003.4UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1049.53UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-hwe-7.07.0.0-28.28~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-ibm6.8.0-1064.65UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-ibm7.0.0-1010.10UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1066.67~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-intel-iotgno fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-kvmno fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-139.139.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-139.139.1~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1062.65UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-nvidia7.0.0-1016.16UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1062.65~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia-7.07.0.0-1016.16~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-nvidia-bos7.0.0-2016.16UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1062.65.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1035.38UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-nvidia-tegra-igxno fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-oem-7.07.0.0-1009.9UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oracle6.8.0-1061.64UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-oracle7.0.0-1008.8UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1061.64~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-oracle-7.07.0.0-1011.11~24.04.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-raspi6.8.0-1064.68UBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-raspi7.0.0-1015.15UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-realtime7.0.0-28.28.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-64138
Ubuntu:26.04:LTSlinux-riscv7.0.0-28.28.1UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-139.139~22.04.1UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-riscv-7.07.0.0-28.28.1~24.04.3UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-vmware6.8.0-1008.8UBUNTU-CVE-2026-64138
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1036.37UBUNTU-CVE-2026-64138
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2026-64138

Affected products (as reported)

VendorProductVersions
Linux Linux e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before f7c4dee323d9176b8d3f5c69018ee57ae0d4653ce2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 8efbea0253b7fa2d1960cab0fed36544ca0b41abe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before f0e5c9c663badc9982e6941322eef1cb17de0f11e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 18d8db24b0a5b7be4829238dd4022236df02d421e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 1c9d0646a9959752f11ca1080dc1ff26bd1756cbe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 – before 69f030cf95488ae1186c72ac8c66fd279664ea7f
Linux Linux 5.15

References