Unity Linux 20.1050a Security Update: kernel (UTSA-2026-100533)

high Nessus Plugin ID 336896

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-2026-100533 advisory.

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

cpufreq: pcc: fix use-after-free and double free in _OSC evaluation

pcc_cpufreq_do_osc() calls acpi_evaluate_object() twice for the two-phase _OSC negotiation. Between the two calls it freed output.pointer but left output.length unchanged. Since acpi_evaluate_object() treats a non-zero length with a non-NULL pointer as an existing buffer to write into, the second call wrote into freed memory (use-after-free). The subsequent kfree(output.pointer) at out_free then freed the same pointer a second time (double free).

Reset output.pointer to NULL and output.length to ACPI_ALLOCATE_BUFFER after freeing the first result, so ACPICA allocates a fresh buffer for each phase independently.

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

https://nvd.nist.gov/vuln/detail/CVE-2026-64372

http://www.nessus.org/u?8b738692

http://www.nessus.org/u?cdb0438f

Plugin Details

Severity: High

ID: 336896

File Name: unity_linux_UTSA-2026-100533.nasl

Version: 1.1

Type: Local

Published: 8/17/2026

Updated: 8/17/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.16

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2026-64372

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/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: 8/13/2026

Vulnerability Publication Date: 7/23/2026

Reference Information

CVE: CVE-2026-64372