Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-013216)

medium Nessus Plugin ID 307962

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-2026-013216 advisory.

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

net: stream: purge sk_error_queue in sk_stream_kill_queues()

Changheon Lee reported TCP socket leaks, with a nice repro.

It seems we leak TCP sockets with the following sequence:

1) SOF_TIMESTAMPING_TX_ACK is enabled on the socket.

Each ACK will cook an skb put in error queue, from __skb_tstamp_tx().
__skb_tstamp_tx() is using skb_clone(), unless SOF_TIMESTAMPING_OPT_TSONLY was also requested.

2) If the application is also using MSG_ZEROCOPY, then we put in the error queue cloned skbs that had a struct ubuf_info attached to them.

Whenever an struct ubuf_info is allocated, sock_zerocopy_alloc() does a sock_hold().

As long as the cloned skbs are still in sk_error_queue, socket refcount is kept elevated.

3) Application closes the socket, while error queue is not empty.

Since tcp_close() no longer purges the socket error queue, we might end up with a TCP socket with at least one skb in error queue keeping the socket alive forever.

This bug can be (ab)used to consume all kernel memory and freeze the host.

We need to purge the error queue, with proper synchronization against concurrent writers.

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: 307962

File Name: unity_linux_UTSA-2026-013216.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

Published: 4/21/2026

Updated: 4/21/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

CVSS Score Source: CVE-2022-50838

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/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: 4/21/2026

Vulnerability Publication Date: 7/21/2021

Reference Information

CVE: CVE-2022-50838

Detections

Analytics