Amazon Linux AMI : squid (ALAS-2020-1453)

High Nessus Plugin ID 142983

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VPR Score: 5.9

Synopsis

The remote Amazon Linux AMI host is missing a security update.

Description

The version of tested product installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2020-1453 advisory.

- An issue was discovered in Squid before 4.10. It allows a crafted FTP server to trigger disclosure of sensitive information from heap memory, such as information associated with other users' sessions or non- Squid processes. (CVE-2019-12528)

- An issue was discovered in http/ContentLengthInterpreter.cc in Squid before 4.12 and 5.x before 5.0.3. A Request Smuggling and Poisoning attack can succeed against the HTTP cache. The client sends an HTTP request with a Content-Length header containing +\ - or an uncommon shell whitespace character prefix to the length field-value. (CVE-2020-15049)

- An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the proxy cache and any downstream caches with content from an arbitrary source. When configured for relaxed header parsing (the default), Squid relays headers containing whitespace characters to upstream servers. When this occurs as a prefix to a Content-Length header, the frame length specified will be ignored by Squid (allowing for a conflicting length to be used from another Content-Length header) but relayed upstream. (CVE-2020-15810)

- An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the browser cache and any downstream caches with content from an arbitrary source. Squid uses a string search instead of parsing the Transfer-Encoding header to find chunked encoding. This allows an attacker to hide a second request inside Transfer-Encoding: it is interpreted by Squid as chunked and split out into a second request delivered upstream. Squid will then deliver two distinct responses to the client, corrupting any downstream caches. (CVE-2020-15811)

- Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during handling of a crafted Cache Digest response message. This only occurs when cache_peer is used with the cache digests feature. The problem exists because peerDigestHandleReply() livelocking in peer_digest.cc mishandles EOF. (CVE-2020-24606)

- An issue was discovered in Squid before 4.10. Due to incorrect input validation, it can interpret crafted HTTP requests in unexpected ways to access server resources prohibited by earlier security filters.
(CVE-2020-8449)

- An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy. (CVE-2020-8450)

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

Solution

Run 'yum update squid' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2020-1453.html

https://access.redhat.com/security/cve/CVE-2019-12528

https://access.redhat.com/security/cve/CVE-2020-15049

https://access.redhat.com/security/cve/CVE-2020-15810

https://access.redhat.com/security/cve/CVE-2020-15811

https://access.redhat.com/security/cve/CVE-2020-24606

https://access.redhat.com/security/cve/CVE-2020-8449

https://access.redhat.com/security/cve/CVE-2020-8450

Plugin Details

Severity: High

ID: 142983

File Name: ala_ALAS-2020-1453.nasl

Version: 1.2

Type: local

Agent: unix

Published: 2020/11/18

Updated: 2020/11/18

Dependencies: 12634

Risk Information

Risk Factor: High

VPR Score: 5.9

CVSS Score Source: CVE-2020-8450

CVSS v2.0

Base Score: 7.5

Temporal Score: 5.5

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

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 7.3

Temporal Score: 6.4

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

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:squid, p-cpe:/a:amazon:linux:squid-debuginfo, p-cpe:/a:amazon:linux:squid-migration-script, cpe:/o:amazon:linux

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

Exploit Ease: No known exploits are available

Patch Publication Date: 2020/11/16

Vulnerability Publication Date: 2020/02/04

Reference Information

CVE: CVE-2019-12528, CVE-2020-8449, CVE-2020-8450, CVE-2020-15049, CVE-2020-15810, CVE-2020-15811, CVE-2020-24606

ALAS: 2020-1453