Squid 3.x < 3.5.6 Multiple Vulnerabilities

high Nessus Network Monitor Plugin ID 8951
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The remote proxy server is affected by multiple vulnerabilities.


Versions of Squid 3.x prior to 3.5.6 are potentially affected by by the following vulnerabilities :

- An authentication bypass vulnerability exists due to a flaw in file 'tunnel.cc', which is triggered whenever cache peer CONNECT responses are blindly forwarded in a hierarchy of two or more proxies, resulting in unrestricted access to a back-end proxy through its gateway proxy. A remote, unauthenticated attacker, using a specially crafted request, can exploit this vulnerability to bypass authentication or gain access to protected resources. This issue occurs in configurations with cache_peer enabled, and exploitation would require that the two proxies have differing levels of security. (CVE-2015-5400)
- A flaw in 'ssl/support.cc' that is triggered during the handling of repeated client-initiated TLS renegotation messages. This may allow a remote attacker to cause a denial of service.


Either upgrade to Squid version 3.5.6 or later, or apply the vendor-supplied patch.

See Also




Plugin Details

Severity: High

ID: 8951

Family: Web Servers

Published: 10/13/2015

Updated: 3/6/2019

Dependencies: 3389

Nessus ID: 84674

Risk Information


Risk Factor: High

Base Score: 7.1

Temporal Score: 5.3

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

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


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

CPE: cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*

Patch Publication Date: 7/3/2015

Vulnerability Publication Date: 7/6/2015

Reference Information

CVE: CVE-2015-5400

BID: 75553