CVE-2026-93811 json
ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling
published last mo. modified last mo. also EUVD-2026-86198
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling
1. When ndr_decode_v4_ntacl() fails, the code jumped to free_n_data which only freed n.data, skipping kfree(acl.sd_buf) and leaking the buffer. Zero-initialize struct xattr_ntacl acl, reorder error labels to out_free to release acl.sd_buf on all error paths.
2. if (acl.sd_size < sizeof(struct smb_ntsd)) is true, original code returned success without freeing sd_buf and left stale *pntsd. Set rc = -EINVAL before jumping to out_free to return error code and free buffer.
Patch / fix
- Linux Linux 5.15.222, 5.19, 5.20, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2
- linux Debian 12 6.1.190-1
- 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-2026-93811
- linux Ubuntu 22.04 LTS 5.15.0-202.212
- linux Ubuntu 24.04 LTS 6.8.0-149.149
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 22.04 LTS 5.15.0-1119.126
- linux-aws Ubuntu 24.04 LTS 6.8.0-1069.74
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 22.04 LTS 5.15.0-1120.130
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1073.81
ubuntu advisories UBUNTU-CVE-2026-93811
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/f46a70a082bdbfecbe074af8a719c26c4deb58c6 commit
- git.kernel.org/stable/c/86c2625fb9863139b359805fc6be1e31edbd3d65 commit
- git.kernel.org/stable/c/edc17db83085624a2b1bacf6a4521d7f15571737 commit
- git.kernel.org/stable/c/c3836f55e0dab96314774215e12d87f63fa919f2 commit
- git.kernel.org/stable/c/6e6329322ad733c5b23555c609353841560b26bc commit
- git.kernel.org/stable/c/d708a36634bb7b6f94d0e76d587d2ec50b2b93b5 commit
Is CVE-2026-93811 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-93811 updated cvss 5.5
kernel: ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling
-
Red Hat Enterprise Linux 10 kernelaffected: no fix available “Fix deferred”
-
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 OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9not affected: vulnerable code not present
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
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/f46a70a082bdbfecbe074af8a719c26c4deb58c6
- git.kernel.org /stable/c/86c2625fb9863139b359805fc6be1e31edbd3d65
- git.kernel.org /stable/c/edc17db83085624a2b1bacf6a4521d7f15571737
- git.kernel.org /stable/c/c3836f55e0dab96314774215e12d87f63fa919f2
- git.kernel.org /stable/c/6e6329322ad733c5b23555c609353841560b26bc
- git.kernel.org /stable/c/d708a36634bb7b6f94d0e76d587d2ec50b2b93b5
Sources
- CVE List CVE-2026-93811
- NVD CVE-2026-93811
Fencer Intel 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.