Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2024-002902)

medium Nessus Plugin ID 338467

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-2024-002902 advisory.

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

KVM: s390: fix setting of fpc register

kvm_arch_vcpu_ioctl_set_fpu() allows to set the floating point control (fpc) register of a guest cpu. The new value is tested for validity by temporarily loading it into the fpc register.

This may lead to corruption of the fpc register of the host process:
if an interrupt happens while the value is temporarily loaded into the fpc register, and within interrupt context floating point or vector registers are used, the current fp/vx registers are saved with save_fpu_regs() assuming they belong to user space and will be loaded into fp/vx registers when returning to user space.

test_fp_ctl() restores the original user space / host process fpc register value, however it will be discarded, when returning to user space.

In result the host process will incorrectly continue to run with the value that was supposed to be used for a guest cpu.

Fix this by simply removing the test. There is another test right before the SIE context is entered which will handles invalid values.

This results in a change of behaviour: invalid values will now be accepted instead of that the ioctl fails with -EINVAL. This seems to be acceptable, given that this interface is most likely not used anymore, and this is in addition the same behaviour implemented with the memory mapped interface (replace invalid values with zero) - see sync_regs() in kvm-s390.c.

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: 338467

File Name: unity_linux_UTSA-2024-002902.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

Published: 8/21/2026

Updated: 8/21/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 2.1

Percentile: 6.91

CVSS v2

Risk Factor: Medium

Base Score: 6.2

Temporal Score: 4.6

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

CVSS Score Source: CVE-2023-52597

CVSS v3

Risk Factor: Medium

Base Score: 4

Temporal Score: 3.5

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

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: 6/6/2024

Vulnerability Publication Date: 2/14/2024

Reference Information

CVE: CVE-2023-52597

Detections

Analytics