CentOS Linux 6 [TuxCare] Security Update: dovecot / dovecot-devel / dovecot-mysql / dovecot-pgsql / etc (CENTOS6:CLSA-2026:1779371000)

high Nessus Plugin ID 361960

Synopsis

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

Description

The CentOS Linux 6 host has packages installed that are affected by a vulnerability as referenced in the TuxCare CENTOS6:CLSA-2026:1779371000 advisory.

- An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known. (CVE-2026-42006)

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 packages based on the guidance in TuxCare advisory CENTOS6:CLSA-2026:1779371000.

See Also

https://cve.tuxcare.com/els/releases/CLSA-2026:1779371000

http://www.nessus.org/u?13046de2

Plugin Details

Severity: High

ID: 361960

File Name: tuxcare_centos_6_CLSA-2026-1779371000.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 10/1/2026

Updated: 10/1/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.76

Vendor

Vendor Severity: Low

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-2026-42006

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/CentOS/release, Host/CentOS/rpm-list, Host/OS/extended-third-party

Exploit Ease: No known exploits are available

Patch Publication Date: 5/21/2026

Vulnerability Publication Date: 5/12/2026

Reference Information

CVE: CVE-2026-42006

CLSA: 2026:1779371000