CentOS 7 : squid (RHSA-2020:2040)

critical Nessus Plugin ID 136774

Synopsis

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

Description

The remote CentOS Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2020:2040 advisory.

- An issue was discovered in Squid through 4.7. When handling the tag esi:when when ESI is enabled, Squid calls ESIExpression::Evaluate. This function uses a fixed stack buffer to hold the expression while it's being evaluated. When processing the expression, it could either evaluate the top of the stack, or add a new member to the stack. When adding a new member, there is no check to ensure that the stack won't overflow. (CVE-2019-12519)

- An issue was discovered in Squid 3.3.9 through 3.5.28 and 4.x through 4.7. When Squid is configured to use Digest authentication, it parses the header Proxy-Authorization. It searches for certain tokens such as domain, uri, and qop. Squid checks if this token's value starts with a quote and ends with one. If so, it performs a memcpy of its length minus 2. Squid never checks whether the value is just a single quote (which would satisfy its requirements), leading to a memcpy of its length minus 1. (CVE-2019-12525)

- An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. This occurs because the attacker can overflow the nonce reference counter (a short integer). Remote code execution may occur if the pooled token credentials are freed (instead of replayed as valid credentials). (CVE-2020-11945)

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 squid, squid-migration-script and / or squid-sysvinit packages.

See Also

https://access.redhat.com/errata/RHSA-2020:2040

Plugin Details

Severity: Critical

ID: 136774

File Name: centos_RHSA-2020-2040.nasl

Version: 1.5

Type: local

Agent: unix

Published: 5/22/2020

Updated: 10/9/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

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

CVSS Score Source: CVE-2020-11945

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

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

Vulnerability Information

CPE: p-cpe:/a:centos:centos:squid-migration-script, cpe:/o:centos:centos:7, p-cpe:/a:centos:centos:squid, p-cpe:/a:centos:centos:squid-sysvinit

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/CentOS/release, Host/CentOS/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 5/21/2020

Vulnerability Publication Date: 7/11/2019

Reference Information

CVE: CVE-2019-12519, CVE-2019-12525, CVE-2020-11945

RHSA: 2020:2040