CentOS Linux 8 [TuxCare] Security Update: rsync / rsync-daemon Multiple Vulnerabilities (CENTOS-STREAM8:CLSA-2026:1788773469)

high Nessus Plugin ID 351507

Synopsis

The CentOS Linux host is missing one or more security updates.

Description

The CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare CENTOS-STREAM8:CLSA-2026:1788773469 advisory.

- rsync before 3.5.0 contains a filter rule bypass vulnerability that allows authenticated clients to override module-level filter restrictions by supplying malicious --filter merge file directives. Attackers can inject client-side merge file directives during filter evaluation to introduce rules that supersede daemon module-level restrictions, gaining access to files the module filter was intended to exclude.
(CVE-2026-53786)

- rsync before 3.5.0 contains an improper path handling vulnerability that allows a malicious sender to expand the scope of --delete operations beyond the intended destination subtree by sending a crafted file list that causes rsync to reclassify implied parent directory entries or treat synthetic paths as the transfer root. Attackers can exploit multiple variants including implied parent reclassification, synthetic root path construction, legacy protocol behavior below version 30, and non-directory root handling to cause the receiver to delete files outside the authorized destination directory.
(CVE-2026-53789)

- rsync 3.0.0 before 3.5.0 contains a null pointer dereference vulnerability in the daemon child process that allows remote attackers to crash the daemon by sending a file list whose first entry is a dot entry not typed as a directory. The daemon dereferences the first file list entry as a directory structure pointer without verifying the entry type, resulting in an invalid or uninitialized pointer dereference that terminates the client connection. (CVE-2026-70459)

- rsync 3.1.0 before 3.5.0 contains an authorization bypass in auth users directive parsing. The auth users parser uses comma-only tokenization when splitting the user list, which fails to correctly handle entries of the form @Group Name where the group name contains a space. The space within the group name causes the parser to split the entry at the space boundary, discarding the deny rule associated with the group. An authenticated user whose username or group membership would be denied by an @Group Name auth users entry can connect to a restricted module because the deny rule is silently discarded during parsing.
(CVE-2026-70463)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages based on the guidance in TuxCare advisory CENTOS-STREAM8:CLSA-2026:1788773469.

See Also

https://cve.tuxcare.com/els/releases/CLSA-2026:1788773469

http://www.nessus.org/u?b5c1efe6

Plugin Details

Severity: High

ID: 351507

File Name: tuxcare_centos_8_CLSA-2026-1788773469.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 9/30/2026

Updated: 9/30/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.43

Vendor

Vendor Severity: Critical

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 7.4

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

CVSS Score Source: CVE-2026-53789

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

CVSS v4

Risk Factor: High

Base Score: 8.6

Threat Score: 7.3

Threat Vector: CVSS:4.0/E:P

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2026-70463

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list, Host/OS/extended-third-party

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 9/7/2026

Vulnerability Publication Date: 8/13/2026

Reference Information

CVE: CVE-2026-53786, CVE-2026-53789, CVE-2026-70459, CVE-2026-70463

CLSA: 2026:1788773469