CVE-2026-89794 json
ksmbd: zero pipe read compound padding
published 2026-09-16 54 d ago modified 2026-10-30 9 d ago also EUVD-2026-80394
- 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 11%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: zero pipe read compound padding
Compound response handling extends the last response iov to an eight-byte boundary.
smb2_read_pipe() allocates only the payload size, so the alignment padding can expose up to seven bytes of uninitialized kernel heap memory.
Allocate the aligned size and clear the unused tail before pinning the response buffer.
Patch / fix
- Linux Linux 5.16, 6.1.191, 6.6.160, 6.12.110, 6.18.51, 7.2.5, 7.3
- 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-2026-89794
- 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-2026-89794
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
- kernel Azure Linux 3.0 6.6.161.1-1
azure linux advisories AZL-101355
Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT
- git.kernel.org/stable/c/c7516bdf7d2c1a64b14a9f444e2ee58c12c384ae commit
- git.kernel.org/stable/c/134d980491b435e5cdb3171225e2506ff17867d1 commit
- git.kernel.org/stable/c/f188a400dd5285fec5a84548fe8dca49eee01155 commit
- git.kernel.org/stable/c/d83a9de7cecd401c3d3e00ed6371194dcd7313e4 commit
- git.kernel.org/stable/c/be15b8da4a82cf1e1f9880b2661b90770606eec1 commit
- git.kernel.org/stable/c/73f860489e3be2245598d1819226304fc5b87291 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-2026-89794 updated cvss 5.5
kernel: ksmbd: zero pipe read compound padding
-
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
0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/c7516bdf7d2c1a64b14a9f444e2ee58c12c384ae
- git.kernel.org /stable/c/134d980491b435e5cdb3171225e2506ff17867d1
- git.kernel.org /stable/c/f188a400dd5285fec5a84548fe8dca49eee01155
- git.kernel.org /stable/c/d83a9de7cecd401c3d3e00ed6371194dcd7313e4
- git.kernel.org /stable/c/be15b8da4a82cf1e1f9880b2661b90770606eec1
- git.kernel.org /stable/c/73f860489e3be2245598d1819226304fc5b87291
Sources
- CVE List CVE-2026-89794
- NVD CVE-2026-89794
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.