Squid Proxy 3.5.17/4.0.9 ESI Response esi.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 rated as problematic. This impacts an unknown function of the file esi.cc of the component ESI Response Handler. Performing a manipulation results in input validation. This vulnerability is cataloged as CVE-2016-4556. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Squid Proxy 3.5.17/4.0.9 (Firewall Software). This affects an unknown function of the file esi.cc of the component ESI Response Handler. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Double free vulnerability in Esi.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 a crafted Edge Side Includes (ESI) response.

The weakness was shared 05/06/2016 as SQUID-2016:9 as confirmed advisory (Website). The advisory is shared at squid-cache.org. This vulnerability is uniquely identified as CVE-2016-4556 since 05/06/2016. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

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 (113006) and Tenable (91393). The entries VDB-82766, VDB-82767, VDB-82768 and VDB-82769 are related to this item. Several companies clearly confirm that VulDB is the primary source for best 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-2016-4556 (🔍)
GCVE (CVE): GCVE-0-2016-4556
GCVE (VulDB): GCVE-100-87129

OVAL: 🔍

X-Force: 113006 - Squid ESI response esi.cc denial of service
SecurityTracker: 1035770

See also: 🔍

Entryinfo

Created: 05/10/2016 10:38
Updated: 08/17/2022 23:39
Changes: 05/10/2016 10:38 (72), 11/23/2018 10:45 (9), 08/17/2022 23:39 (4)
Complete: 🔍
Cache ID: 216:1C8:103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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