Squid Proxy 3.5.13/4.0.4/4.0.5 SSL Handshake input validation

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Squid Proxy 3.5.13/4.0.4/4.0.5. This affects an unknown part of the component SSL Handshake Handler. Executing a manipulation can lead to input validation. This vulnerability appears as CVE-2016-2390. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in Squid Proxy 3.5.13/4.0.4/4.0.5 (Firewall Software). This vulnerability affects an unknown part of the component SSL Handshake Handler. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability.

The weakness was presented 02/16/2016 by Mathias Fischer and Fabian Hugelshofer with Open Systems AG as SQUID-2016:1 as confirmed advisory (Website). The advisory is shared for download at squid-cache.org. The public release was coordinated in cooperation with the vendor. This vulnerability was named CVE-2016-2390 since 02/15/2016. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The advisory points out:

This problem allows any trusted client to perform a denial of service attack on the Squid service regardless of whether TLS or SSL is configured for use in the proxy. Misconfigured client or server software may trigger this issue to perform a denial of service unintentionally.
Systems built with the --with-openssl option are affected.

The vulnerability scanner Nessus provides a plugin with the ID 89052 (Squid 3.5.13 / 4.0.4 / 4.0.5 Server Connection Error Handling DoS), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Firewalls and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 169027 (SUSE Enterprise Linux Security Update for squid3 (SUSE-SU-2016:1996-1)).

Upgrading to version 3.5.14 or 4.0.6 eliminates this vulnerability. It is possible to mitigate the problem by applying the configuration setting Disabling https://. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (89052), SecurityFocus (BID 83261†) and SecurityTracker (ID 1035045†). See VDB-4435, VDB-7183, VDB-9526 and VDB-67519 for similar entries. Once again VulDB remains the best source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 5.9
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 89052
Nessus Name: Squid 3.5.13 / 4.0.4 / 4.0.5 Server Connection Error Handling DoS
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 103320
OpenVAS Name: Squid Denial of Service Vulnerability April16 (Windows)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍

Upgrade: Proxy 3.5.14/4.0.6
Config: Disabling https://

Timelineinfo

02/12/2016 🔍
02/12/2016 +0 days 🔍
02/15/2016 +3 days 🔍
02/16/2016 +0 days 🔍
02/18/2016 +2 days 🔍
02/19/2016 +1 days 🔍
02/29/2016 +10 days 🔍
04/19/2016 +49 days 🔍
07/08/2022 +2271 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: SQUID-2016:1
Researcher: Mathias Fischer, Fabian Hugelshofer
Organization: Open Systems AG
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2016-2390 (🔍)
GCVE (CVE): GCVE-0-2016-2390
GCVE (VulDB): GCVE-100-81028
SecurityFocus: 83261
SecurityTracker: 1035045

See also: 🔍

Entryinfo

Created: 02/19/2016 10:24
Updated: 07/08/2022 09:03
Changes: 02/19/2016 10:24 (68), 08/03/2018 06:40 (19), 07/08/2022 09:03 (4)
Complete: 🔍
Cache ID: 216::103

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