Unity Linux 20.1050e Security Update: kernel (UTSA-2026-007450)

critical Nessus Plugin ID 307126

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-2026-007450 advisory.

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

ubi: Fix use-after-free when volume resizing failed

There is an use-after-free problem reported by KASAN:
================================================================== BUG: KASAN: use-after-free in ubi_eba_copy_table+0x11f/0x1c0 [ubi] Read of size 8 at addr ffff888101eec008 by task ubirsvol/4735

CPU: 2 PID: 4735 Comm: ubirsvol Not tainted 6.1.0-rc1-00003-g84fa3304a7fc-dirty #14 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace:
<TASK> dump_stack_lvl+0x34/0x44 print_report+0x171/0x472 kasan_report+0xad/0x130 ubi_eba_copy_table+0x11f/0x1c0 [ubi] ubi_resize_volume+0x4f9/0xbc0 [ubi] ubi_cdev_ioctl+0x701/0x1850 [ubi]
__x64_sys_ioctl+0x11d/0x170 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 </TASK>

When ubi_change_vtbl_record() returns an error in ubi_resize_volume(), new_eba_tbl will be freed on error handing path, but it is holded by vol->eba_tbl in ubi_eba_replace_table(). It means that the liftcycle of vol->eba_tbl and vol are different, so when resizing volume in next time, it causing an use-after-free fault.

Fix it by not freeing new_eba_tbl after it replaced in ubi_eba_replace_table(), while will be freed in next volume resizing.

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: Critical

ID: 307126

File Name: unity_linux_UTSA-2026-007450.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

Published: 4/17/2026

Updated: 4/17/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

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

CVSS Score Source: CVE-2023-53800

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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: 4/17/2026

Vulnerability Publication Date: 7/21/2021

Reference Information

CVE: CVE-2023-53800

Detections

Analytics