Unity Linux 20.1050e Security Update: kernel (UTSA-2026-099790)

high Nessus Plugin ID 336131

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-2026-099790 advisory.

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

tee: optee: prevent use-after-free when the client exits before the supplicant

Commit 70b0d6b0a199 (tee: optee: Fix supplicant wait loop) made the client wait as killable so it can be interrupted during shutdown or after a supplicant crash. This changes the original lifetime expectations:
the client task can now terminate while the supplicant is still processing its request.

If the client exits first it removes the request from its queue and kfree()s it, while the request ID remains in supp->idr. A subsequent lookup on the supplicant path then dereferences freed memory, leading to a use-after-free.

Serialise access to the request with supp->mutex:

* Hold supp->mutex in optee_supp_recv() and optee_supp_send() while looking up and touching the request.
* Let optee_supp_thrd_req() notice that the client has terminated and signal optee_supp_send() accordingly.

With these changes the request cannot be freed while the supplicant still has a reference, eliminating the race.

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: High

ID: 336131

File Name: unity_linux_UTSA-2026-099790.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

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-2026-53273

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: 6/25/2026

Reference Information

CVE: CVE-2026-53273

Detections

Analytics