Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098710)

medium Nessus Plugin ID 340384

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-098710 advisory.

In the Linux kernel, the following vulnerability has been resolved:

NFSD: fix race between nfsd registration and exports_proc

As of now nfsd calls create_proc_exports_entry() at start of init_nfsd and cleanup by remove_proc_entry() at last of exit_nfsd.

Which causes kernel OOPs if there is race between below 2 operations:
(i) exportfs -r (ii) mount -t nfsd none /proc/fs/nfsd

for 5.4 kernel ARM64:

CPU 1:
el1_irq+0xbc/0x180 arch_counter_get_cntvct+0x14/0x18 running_clock+0xc/0x18 preempt_count_add+0x88/0x110 prep_new_page+0xb0/0x220 get_page_from_freelist+0x2d8/0x1778
__alloc_pages_nodemask+0x15c/0xef0
__vmalloc_node_range+0x28c/0x478
__vmalloc_node_flags_caller+0x8c/0xb0 kvmalloc_node+0x88/0xe0 nfsd_init_net+0x6c/0x108 [nfsd] ops_init+0x44/0x170 register_pernet_operations+0x114/0x270 register_pernet_subsys+0x34/0x50 init_nfsd+0xa8/0x718 [nfsd] do_one_initcall+0x54/0x2e0

CPU 2 :
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010

PC is at : exports_net_open+0x50/0x68 [nfsd]

Call trace:
exports_net_open+0x50/0x68 [nfsd] exports_proc_open+0x2c/0x38 [nfsd] proc_reg_open+0xb8/0x198 do_dentry_open+0x1c4/0x418 vfs_open+0x38/0x48 path_openat+0x28c/0xf18 do_filp_open+0x70/0xe8 do_sys_open+0x154/0x248

Sometimes it crashes at exports_net_open() and sometimes cache_seq_next_rcu().

and same is happening on latest 6.14 kernel as well:

[ 0.000000] Linux version 6.14.0-rc5-next-20250304-dirty ...
[ 285.455918] Unable to handle kernel paging request at virtual address 00001f4800001f48 ...
[ 285.464902] pc : cache_seq_next_rcu+0x78/0xa4 ...
[ 285.469695] Call trace:
[ 285.470083] cache_seq_next_rcu+0x78/0xa4 (P) [ 285.470488] seq_read+0xe0/0x11c [ 285.470675] proc_reg_read+0x9c/0xf0 [ 285.470874] vfs_read+0xc4/0x2fc [ 285.471057] ksys_read+0x6c/0xf4 [ 285.471231] __arm64_sys_read+0x1c/0x28 [ 285.471428] invoke_syscall+0x44/0x100 [ 285.471633] el0_svc_common.constprop.0+0x40/0xe0 [ 285.471870] do_el0_svc_compat+0x1c/0x34 [ 285.472073] el0_svc_compat+0x2c/0x80 [ 285.472265] el0t_32_sync_handler+0x90/0x140 [ 285.472473] el0t_32_sync+0x19c/0x1a0 [ 285.472887] Code: f9400885 93407c23 937d7c27 11000421 (f86378a3) [ 285.473422] ---[ end trace 0000000000000000 ]---

It reproduced simply with below script:
while [ 1 ] do /exportfs -r done &

while [ 1 ] do insmod /nfsd.ko mount -t nfsd none /proc/fs/nfsd umount /proc/fs/nfsd rmmod nfsd done &

So exporting interfaces to user space shall be done at last and cleanup at first place.

With change there is no Kernel OOPs.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected kernel package.

Plugin Details

Severity: Medium

ID: 340384

File Name: unity_linux_UTSA-2026-098710.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

Published: 8/26/2026

Updated: 8/26/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.76

CVSS v2

Risk Factor: Low

Base Score: 3.8

Temporal Score: 2.8

Vector: CVSS2#AV:L/AC:H/Au:S/C:N/I:N/A:C

CVSS Score Source: CVE-2025-38232

CVSS v3

Risk Factor: Medium

Base Score: 4.7

Temporal Score: 4.1

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/10/2026

Vulnerability Publication Date: 7/4/2025

Reference Information

CVE: CVE-2025-38232

Detections

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