CVE-2026-93786 json
ksmbd: preserve VFS inherited POSIX ACL mask
published 2026-09-24 45 d ago modified 2026-10-30 9 d ago also EUVD-2026-86173
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: preserve VFS inherited POSIX ACL mask
The VFS initializes a child's POSIX ACL from the parent's default ACL and the requested creation mode. Do not mutate the parent ACL or overwrite the child's VFS-computed access and default ACLs afterwards.
This preserves restrictive ACL_MASK entries and prevents SMB object creation from widening effective permissions.
Patch / fix
- Linux Linux 6.1.191, 6.6.158, 6.12.111, 6.18.53, 7.2
- linux Debian 13 6.12.111-1
- linux Debian 14 7.2.6-1
- linux-6.12 Debian 12 6.12.111-1~deb12u1
debian advisories DEBIAN-CVE-2026-93786
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
- linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
- linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
- linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
- linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
- linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17
ubuntu advisories UBUNTU-CVE-2026-93786
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- git.kernel.org/stable/c/8493da704275ca5ab67fb88c0ae7b71576e91951 commit
- git.kernel.org/stable/c/4a19bb1c45667f5a5f6eff9cf6648e0f692d046f commit
- git.kernel.org/stable/c/591acf171644de590cda245fd8595b473a1beb70 commit
- git.kernel.org/stable/c/0093909becbda22b62b39b654dbc607faed59cd0 commit
- git.kernel.org/stable/c/e148e567a9252643baa125cb65d7ae9c2c6cf68a commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-93786 updated cvss 5.5
kernel: ksmbd: preserve VFS inherited POSIX ACL mask
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9not affected: vulnerable code not present
+1 more productsfewer
Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/8493da704275ca5ab67fb88c0ae7b71576e91951
- git.kernel.org /stable/c/4a19bb1c45667f5a5f6eff9cf6648e0f692d046f
- git.kernel.org /stable/c/591acf171644de590cda245fd8595b473a1beb70
- git.kernel.org /stable/c/0093909becbda22b62b39b654dbc607faed59cd0
- git.kernel.org /stable/c/e148e567a9252643baa125cb65d7ae9c2c6cf68a
Sources
- CVE List CVE-2026-93786
- NVD CVE-2026-93786
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.