Unity Linux 20.1070e Security Update: kernel (UTSA-2026-013131)

medium Nessus Plugin ID 308031

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-2026-013131 advisory.

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

vmci_host: fix a race condition in vmci_host_poll() causing GPF

During fuzzing, a general protection fault is observed in vmci_host_poll().

general protection fault, probably for non-canonical address 0xdffffc0000000019: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf] RIP: 0010:__lock_acquire+0xf3/0x5e00 kernel/locking/lockdep.c:4926 <- omitting registers -> Call Trace:
<TASK> lock_acquire+0x1a4/0x4a0 kernel/locking/lockdep.c:5672
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb3/0x100 kernel/locking/spinlock.c:162 add_wait_queue+0x3d/0x260 kernel/sched/wait.c:22 poll_wait include/linux/poll.h:49 [inline] vmci_host_poll+0xf8/0x2b0 drivers/misc/vmw_vmci/vmci_host.c:174 vfs_poll include/linux/poll.h:88 [inline] do_pollfd fs/select.c:873 [inline] do_poll fs/select.c:921 [inline] do_sys_poll+0xc7c/0x1aa0 fs/select.c:1015
__do_sys_ppoll fs/select.c:1121 [inline]
__se_sys_ppoll+0x2cc/0x330 fs/select.c:1101 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4e/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Example thread interleaving that causes the general protection fault is as follows:

CPU1 (vmci_host_poll) CPU2 (vmci_host_do_init_context)
----- ----- // Read uninitialized context context = vmci_host_dev->context;
// Initialize context vmci_host_dev->context = vmci_ctx_create();
vmci_host_dev->ct_type = VMCIOBJ_CONTEXT;

if (vmci_host_dev->ct_type == VMCIOBJ_CONTEXT) { // Dereferencing the wrong pointer poll_wait(..., &context->host_context);
}

In this scenario, vmci_host_poll() reads vmci_host_dev->context first, and then reads vmci_host_dev->ct_type to check that vmci_host_dev->context is initialized. However, since these two reads are not atomically executed, there is a chance of a race condition as described above.

To fix this race condition, read vmci_host_dev->context after checking the value of vmci_host_dev->ct_type so that vmci_host_poll() always reads an initialized context.

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.

See Also

http://www.nessus.org/u?b9a6bd1b

http://www.nessus.org/u?aa781e0d

https://nvd.nist.gov/vuln/detail/CVE-2023-54007

Plugin Details

Severity: Medium

ID: 308031

File Name: unity_linux_UTSA-2026-013131.nasl

Version: 1.1

Type: Local

Published: 4/21/2026

Updated: 4/21/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

CVSS Score Source: CVE-2023-54007

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/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: 4/21/2026

Vulnerability Publication Date: 7/21/2021

Reference Information

CVE: CVE-2023-54007