CVE-2026-89484 json
lockd: fix NULL dereference on lockowner allocation failure
published 2026-09-11 58 d ago modified 2026-10-30 9 d ago also EUVD-2026-76390
- 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:
lockd: fix NULL dereference on lockowner allocation failure
nlmclnt_locks_init_private() installs NLM file lock operations even when nlmclnt_find_lockowner() fails to allocate a lockowner. nlmclnt_proc() then returns -ENOMEM, but the VFS still tears down the partially initialized file_lock and calls locks_release_private().
That invokes nlmclnt_locks_release_private(), which dereferences fl->fl_u.nfs_fl.owner and crashes because the owner was never installed.
Clear fl_ops before attempting to initialize the NLM private state, and install the NLM lock operations only after a lockowner has been allocated successfully.
Patch / fix
- Linux Linux 6.1.191, 6.6.160, 6.12.109, 6.18.50, 7.2.4, 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-2026-89484
- 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-2026-89484
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-source openSUSE Tumbleweed 7.2.6-1.1
opensuse advisories openSUSE-SU-2026:11805-1
- kernel Azure Linux 3.0 6.6.161.1-1
azure linux advisories AZL-100778
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/b61053a3795c2913a7af3ab6218acfdaf52fcafe commit
- git.kernel.org/stable/c/6db5af172ccc3223c8f730a9a4212f6427feee3e commit
- git.kernel.org/stable/c/07adfbb3de7529f58ca708a97ead7fa4fdb71056 commit
- git.kernel.org/stable/c/d662f7fc04fde305a27f304b3cd19b614d366839 commit
- git.kernel.org/stable/c/51af080ca4e553256c59a75a877b9b4fff828311 commit
- git.kernel.org/stable/c/4c7fc129db061c7daab841c4f3c342d894832362 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-2026-89484 updated cvss 5.5
kernel: lockd: fix NULL dereference on lockowner allocation failure
-
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-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9affected: workaround, 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 OpenShift Container Platform 4 openshift/ose-rhel-coreos-8not 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
0.21% 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/b61053a3795c2913a7af3ab6218acfdaf52fcafe
- git.kernel.org /stable/c/6db5af172ccc3223c8f730a9a4212f6427feee3e
- git.kernel.org /stable/c/07adfbb3de7529f58ca708a97ead7fa4fdb71056
- git.kernel.org /stable/c/d662f7fc04fde305a27f304b3cd19b614d366839
- git.kernel.org /stable/c/51af080ca4e553256c59a75a877b9b4fff828311
- git.kernel.org /stable/c/4c7fc129db061c7daab841c4f3c342d894832362
Sources
- CVE List CVE-2026-89484
- NVD CVE-2026-89484
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.