Squid < 3.5.18 Host Header Handling Same-Origin Protection / Content Filtering Bypass (SQUID-2016:8)

high Nessus Plugin ID 108809
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Synopsis

The remote proxy server is potentially affected by a same-origin filtering bypass vulnerability.

Description

According to its banner, the version of Squid running on the remote host is prior to 3.5.18. It is, therefore, potentially affected by a Host header same-origin filtering bypass vulnerability. A remote attacker could exploit this issue to poison the cache by forcing a Host header value past same-origin security protections to cause Squid to contact the wrong origin server.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
Furthermore, the patch released to address this issue does not update the version given in the banner. If the patch has been applied properly, and the service has been restarted, then consider this to be a false positive.

Solution

Upgrade to Squid version 3.5.18 or later. Alternatively, apply the vendor-supplied patch.

See Also

http://www.squid-cache.org/Advisories/SQUID-2016_8.txt

Plugin Details

Severity: High

ID: 108809

File Name: squid_3_5_18.nasl

Version: 1.4

Type: remote

Family: Firewalls

Published: 4/3/2018

Updated: 12/17/2018

Dependencies: squid_version.nasl

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2016-4554

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

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

CVSS v3

Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

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

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

Vulnerability Information

CPE: cpe:/a:squid-cache:squid

Required KB Items: installed_sw/Squid, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 5/6/2016

Vulnerability Publication Date: 5/6/2016

Reference Information

CVE: CVE-2016-4554