Unity Linux 20.1050a Security Update: kernel (UTSA-2026-146617)

high Nessus Plugin ID 373152

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-2026-146617 advisory.

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

net: skbuff: don't touch shared zerocopy state in skb_tx_error()

skb_tx_error() completes the zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, and skb_zcopy_downgrade_managed() clears SKBFL_MANAGED_FRAG_REFS. Both live in skb_shinfo(), which every clone shares, while the caller only owns the reference it is about to drop.
Through a clone it tells the producer its pages are free and drops SKBFL_SHARED_FRAG for an skb that is still in flight.

Open vSwitch reaches this with a non-last OVS_ACTION_ATTR_RECIRC:
clone_execute() sends a skb_clone() into ovs_dp_process_packet() while do_execute_actions() keeps forwarding the original, and skb_clone() does not privatise the frags here -- skb_orphan_frags() returns early on SKBFL_DONT_ORPHAN. A flow miss on the clone then strips the marker from the packet still being forwarded, and a later local ESP delivery decrypts in place over frags it does not own privately.

Skip it for a cloned skb. Nothing is lost: skb_release_data() clears the zerocopy state once the last reference to the shared data goes.

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-2026-80977

http://www.nessus.org/u?9c3af2ac

http://www.nessus.org/u?e89e8024

Plugin Details

Severity: High

ID: 373152

File Name: unity_linux_UTSA-2026-146617.nasl

Version: 1.2

Type: Local

Published: 10/28/2026

Updated: 10/29/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.54

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-2026-80977

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: 10/28/2026

Vulnerability Publication Date: 9/11/2026

Reference Information

CVE: CVE-2026-80977