Unity Linux 20.1050e Security Update: kernel (UTSA-2026-099785)

high Nessus Plugin ID 336233

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-2026-099785 advisory.

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

sctp: stream: fully roll back denied add-stream state

When ADD_OUT_STREAMS is denied, SCTP only shrinks the queued chunks and then lowers outcnt. That leaves removed stream metadata behind, so a later re-add can reuse a stale ext and hit a null-pointer dereference in the scheduler get path.

Fix the rollback by tearing down the removed stream state the same way other stream resizes do. Unschedule the current scheduler state, drop the removed stream ext state with sctp_stream_outq_migrate(), and then reschedule the remaining streams.

This keeps scheduler-private RR/FC/PRIO lists consistent while fully rolling back denied outgoing stream additions.

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-2026-52929

http://www.nessus.org/u?4235ebb3

http://www.nessus.org/u?f14bc9d9

Plugin Details

Severity: High

ID: 336233

File Name: unity_linux_UTSA-2026-099785.nasl

Version: 1.1

Type: Local

Published: 8/17/2026

Updated: 8/17/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.71

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-52929

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

Vulnerability Publication Date: 6/24/2026

Reference Information

CVE: CVE-2026-52929