Debian DLA-2394-1 : squid3 security update

Medium Nessus Plugin ID 141136

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VPR Score: 5.9

Synopsis

The remote Debian host is missing a security update.

Description

Several security vulnerabilities have been discovered in Squid, a high- performance proxy caching server for web clients.

CVE-2020-15049

An issue was discovered in http/ContentLengthInterpreter.cc in Squid.
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. This update also includes several other improvements to the HttpHeader parsing code.

CVE-2020-15810 and CVE-2020-15811

Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning and 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-2020-24606

Squid 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.

For Debian 9 stretch, these problems have been fixed in version 3.5.23-5+deb9u5.

We recommend that you upgrade your squid3 packages.

For the detailed security status of squid3 please refer to its security tracker page at:
https://security-tracker.debian.org/tracker/squid3

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Upgrade the affected packages.

See Also

https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html

https://packages.debian.org/source/stretch/squid3

https://security-tracker.debian.org/tracker/source-package/squid3

Plugin Details

Severity: Medium

ID: 141136

File Name: debian_DLA-2394.nasl

Version: 1.2

Type: local

Agent: unix

Published: 2020/10/05

Updated: 2020/10/07

Dependencies: 12634

Risk Information

Risk Factor: Medium

VPR Score: 5.9

CVSS Score Source: CVE-2020-15049

CVSS v2.0

Base Score: 6.5

Temporal Score: 4.8

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

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

CVSS v3.0

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/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:debian:debian_linux:squid, p-cpe:/a:debian:debian_linux:squid-cgi, p-cpe:/a:debian:debian_linux:squid-common, p-cpe:/a:debian:debian_linux:squid-dbg, p-cpe:/a:debian:debian_linux:squid-purge, p-cpe:/a:debian:debian_linux:squid3, p-cpe:/a:debian:debian_linux:squidclient, cpe:/o:debian:debian_linux:9.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 2020/10/02

Vulnerability Publication Date: 2020/06/30

Reference Information

CVE: CVE-2020-15049, CVE-2020-15810, CVE-2020-15811, CVE-2020-24606