Vulnerability · Published Jul 25, 2026 · Assigned by Linux

CVE-2026-64379smb: client: mask server-provided mode to 07777 in modefromsid

High 7.1

In plain English

A high-severity improper input validation 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 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.1High
Exploit odds (30 days)0.3%top 76.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

In the Linux kernel, the following vulnerability has been resolved: smb: client: mask server-provided mode to 07777 in modefromsid When modefromsid is active, parse_dacl() applies the server-provided sub_auth[2] value from the NFS mode SID to cf_mode without masking to 07777. Apply the correct masking, same as in the read path.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8bpftool4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:10kernel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-devel-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-devel-matched5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-debug-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-debug-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-devel-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-devel-matched5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-64k-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-64k-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-abi-stablelists6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-abi-stablelists4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-abi-stablelists5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-core4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-cross-headers6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-cross-headers4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-cross-headers5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-debug4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-debug5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-debug-core4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-debug-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-debug-devel4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-debug-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-devel-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-debug-devel-matched5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-debug-modules4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-debug-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-debug-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-debug-modules-extra4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-debug-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-debug-uki-virt6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-debug-uki-virt5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-devel4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-devel-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-devel-matched5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-doc6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-doc4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-doc5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-headers6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-headers4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-headers5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-modules4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-modules-extra4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-modules-extra-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:10kernel-rt6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-debug-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-debug-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-64k-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-64k-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-core4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-debug4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-debug5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-debug-core4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-debug-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-debug-devel4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-debug-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-debug-modules4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-debug-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-debug-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-debug-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-debug-modules-extra4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-debug-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-devel4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-modules4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-rt-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-rt-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-rt-modules-extra4.18.0-553.157.1.rt7.498.el8_10ALSA-2026:57254
AlmaLinux:9kernel-rt-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-tools6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-tools4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-tools5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-tools-libs6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-tools-libs4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-tools-libs5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-tools-libs-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-tools-libs-devel4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-tools-libs-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-uki-virt6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-uki-virt5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-uki-virt-addons6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-uki-virt-addons5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-zfcpdump4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-zfcpdump5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-zfcpdump-core4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-zfcpdump-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-devel6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-zfcpdump-devel4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-zfcpdump-devel5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-devel-matched6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-zfcpdump-devel-matched5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-modules6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-zfcpdump-modules4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-zfcpdump-modules5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-modules-core6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9kernel-zfcpdump-modules-core5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10kernel-zfcpdump-modules-extra6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8kernel-zfcpdump-modules-extra4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9kernel-zfcpdump-modules-extra5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10libperf6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9libperf5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10perf6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8perf4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9perf5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10python3-perf6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:8python3-perf4.18.0-553.157.1.el8_10ALSA-2026:57253
AlmaLinux:9python3-perf5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10rtla6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9rtla5.14.0-687.41.1.el9_8ALSA-2026:57252
AlmaLinux:10rv6.12.0-211.49.1.el10_2ALSA-2026:57251
AlmaLinux:9rv5.14.0-687.41.1.el9_8ALSA-2026:57252
Debian:12linux6.1.180-1DEBIAN-CVE-2026-64379
Debian:13linux6.12.96-1DEBIAN-CVE-2026-64379
Debian:14linux7.1.4-1DEBIAN-CVE-2026-64379
Debian:12linux-6.126.12.100-1~deb12u1DEBIAN-CVE-2026-64379
Rocky Linux:10kernel0:6.12.0-211.49.1.el10_2RLSA-2026:57251
Rocky Linux:8kernel0:4.18.0-553.157.1.el8_10RLSA-2026:57253
Rocky Linux:9kernel0:5.14.0-687.41.1.el9_8RLSA-2026:57252
Rocky Linux:8kernel-rt0:4.18.0-553.157.1.rt7.498.el8_10RLSA-2026:57254
Ubuntu:22.04:LTSlinux5.15.0-198.208UBUNTU-CVE-2026-64379
Ubuntu:24.04:LTSlinux6.8.0-147.147UBUNTU-CVE-2026-64379
Ubuntu:26.04:LTSlinux7.0.0-31.31UBUNTU-CVE-2026-64379
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-64379
Ubuntu:22.04:LTSlinux-aws5.15.0-1117.124UBUNTU-CVE-2026-64379
Ubuntu:24.04:LTSlinux-aws6.8.0-1067.70UBUNTU-CVE-2026-64379
Ubuntu:26.04:LTSlinux-aws7.0.0-1012.12UBUNTU-CVE-2026-64379
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-64379

Affected products (as reported)

VendorProductVersions
Linux Linux e2f8fbfb8d09c06decde162090fac3ee220aa280 – before 5f6f2241034f189c69d4d0b5f8fe24a0c25b0c14e2f8fbfb8d09c06decde162090fac3ee220aa280 – before ee2216dbdf0c677e89bb43e03247dba590ed00efe2f8fbfb8d09c06decde162090fac3ee220aa280 – before f511807feee7cb29b61bdfa86472c7e9e2e5df94e2f8fbfb8d09c06decde162090fac3ee220aa280 – before 08c600b7e1818539ba5efee4cdb06215c245ca78e2f8fbfb8d09c06decde162090fac3ee220aa280 – before b84e002e0df26bbc6cbd3ca01b8212601fe0ae7de2f8fbfb8d09c06decde162090fac3ee220aa280 – before c6c484a7d5bff6b929a86d7ed5130f29834c6a0de2f8fbfb8d09c06decde162090fac3ee220aa280 – before f80add1bfb3425100a325b14f19648e75669a954e2f8fbfb8d09c06decde162090fac3ee220aa280 – before e3d9c7160d483fc8f9e225aafad8ecbbc43f3151
Linux Linux 5.4

Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H

References