Detections
Analytics

Unity Linux 20.1050e Security Update: kernel (UTSA-2026-100159)

medium Nessus Plugin ID 336144

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-2026-100159 advisory.

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

 netfilter: nf_conntrack_h323: Add protection for bmp length out of range

 UBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts that are out of bounds for their data type.

 vmlinux get_bitmap(b=75) + 712 <net/netfilter/nf_conntrack_h323_asn1.c:0> vmlinux decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956 <net/netfilter/nf_conntrack_h323_asn1.c:592> vmlinux decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216 <net/netfilter/nf_conntrack_h323_asn1.c:814> vmlinux decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812 <net/netfilter/nf_conntrack_h323_asn1.c:576> vmlinux decode_choice(base=0xFFFFFFD008037280, level=0) + 1216 <net/netfilter/nf_conntrack_h323_asn1.c:814> vmlinux DecodeRasMessage() + 304 <net/netfilter/nf_conntrack_h323_asn1.c:833> vmlinux ras_help() + 684 <net/netfilter/nf_conntrack_h323_main.c:1728> vmlinux nf_confirm() + 188 <net/netfilter/nf_conntrack_proto.c:137>

 Due to abnormal data in skb->data, the extension bitmap length exceeds 32 when decoding ras message then uses the length to make a shift operation. It will change into negative after several loop.
 UBSAN load could detect a negative shift as an undefined behaviour and reports exception.
 So we add the protection to avoid the length exceeding 32. Or else it will return out of range error and stop decoding.

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-2024-26851

http://www.nessus.org/u?c0be2020

http://www.nessus.org/u?ed69910f

Plugin Details

Severity: Medium

ID: 336144

File Name: unity_linux_UTSA-2026-100159.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: 23.18

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-2024-26851

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: 8/13/2026

Vulnerability Publication Date: 4/9/2024

Reference Information

CVE: CVE-2024-26851