Squid Proxy 3.5.17/4.0.9 ESI Response client_side_request.cc input validation

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Squid Proxy 3.5.17/4.0.9. It has been classified as problematic. The impacted element is an unknown function of the file client_side_request.cc of the component ESI Response Handler. This manipulation causes input validation. This vulnerability is tracked as CVE-2016-4555. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Squid Proxy 3.5.17/4.0.9 (Firewall Software). It has been declared as critical. Affected by this vulnerability is an unknown code block of the file client_side_request.cc of the component ESI Response 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 confidentiality, integrity, and availability. The summary by CVE is:

client_side_request.cc in Squid 3.x before 3.5.18 and 4.x before 4.0.10 allows remote servers to cause a denial of service (crash) via crafted Edge Side Includes (ESI) responses.

The weakness was disclosed 05/06/2016 as SQUID-2016:9 as confirmed advisory (Website). It is possible to read the advisory at squid-cache.org. This vulnerability is known as CVE-2016-4555 since 05/06/2016. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 91393 (CentOS 6 : squid34 (CESA-2016:1140)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CentOS Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 236019 (Red Hat Update for Squid 3.4 (RHSA-2016:1140)).

Upgrading to version 3.5.18 or 4.0.10 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (113002) and Tenable (91393). The entries VDB-82766, VDB-82767, VDB-82768 and VDB-82769 are pretty similar. Be aware that VulDB is the high quality 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: 8.2
VulDB Meta Temp Score: 7.6

VulDB Base Score: 8.8
VulDB Temp Score: 7.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
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: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 91393
Nessus Name: CentOS 6 : squid34 (CESA-2016:1140)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703036
OpenVAS Name: Squid Multiple Denial of Service Vulnerabilities-01 May16 (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: 🔍
Exposure Time: 🔍

Upgrade: Proxy 3.5.18/4.0.10

Timelineinfo

05/06/2016 🔍
05/06/2016 +0 days 🔍
05/06/2016 +0 days 🔍
05/10/2016 +4 days 🔍
05/10/2016 +0 days 🔍
06/01/2016 +22 days 🔍
08/17/2022 +2268 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: SQUID-2016:9
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-4555 (🔍)
GCVE (CVE): GCVE-0-2016-4555
GCVE (VulDB): GCVE-100-87127

OVAL: 🔍

X-Force: 113002 - SQUID ESI Response client_side_request.cc denial of service
SecurityTracker: 1035770

See also: 🔍

Entryinfo

Created: 05/10/2016 10:37
Updated: 08/17/2022 23:16
Changes: 05/10/2016 10:37 (72), 11/23/2018 10:45 (9), 08/17/2022 23:16 (4)
Complete: 🔍
Cache ID: 216::103

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