Squid Proxy up to 4.0.22 HTTP Header X-Forwarded-For null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in Squid Proxy up to 4.0.22. This issue affects some unknown processing of the component HTTP Header Handler. Performing a manipulation of the argument X-Forwarded-For as part of HTTP Response results in null pointer dereference. This vulnerability was named CVE-2018-1000027. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Squid Proxy up to 4.0.22 (Firewall Software). It has been classified as problematic. This affects some unknown functionality of the component HTTP Header Handler. The manipulation of the argument X-Forwarded-For as part of a HTTP Response leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.

The bug was discovered 01/19/2018. The weakness was presented 02/09/2018 with Qihoo 360 Vulcan Team (Website). The advisory is shared at squid-cache.org. This vulnerability is uniquely identified as CVE-2018-1000027 since 01/29/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 21 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 106957 (Debian DSA-4122-1 : squid3 - security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176303 (Debian Security Update for squid3 (DSA 4122-1)).

Upgrading to version 4.0.23 eliminates this vulnerability. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (106957) and SecurityFocus (BID 103603†). See VDB-110554, VDB-113070, VDB-114085 and VDB-114440 for similar entries. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
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: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 106957
Nessus Name: Debian DSA-4122-1 : squid3 - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 860773
OpenVAS Name: Squid Proxy Cache Security Update Advisory SQUID-2018:2 (Linux)
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 4.0.23
Patch: github.com

Timelineinfo

01/19/2018 🔍
01/29/2018 +10 days 🔍
02/09/2018 +11 days 🔍
02/09/2018 +0 days 🔍
02/10/2018 +1 days 🔍
02/23/2018 +13 days 🔍
02/23/2018 +0 days 🔍
04/10/2018 +46 days 🔍
02/06/2023 +1763 days 🔍

Sourcesinfo

Vendor: squid-cache.org

Advisory: USN-3557-1
Researcher: Yuki Chen
Organization: Qihoo 360 Vulcan Team
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-1000027 (🔍)
GCVE (CVE): GCVE-0-2018-1000027
GCVE (VulDB): GCVE-100-113073

OVAL: 🔍

SecurityFocus: 103603 - Microsoft Internet Explorer Scripting Engine CVE-2018-1000 Information Disclosure Vulnerability

See also: 🔍

Entryinfo

Created: 02/10/2018 09:20
Updated: 02/06/2023 10:06
Changes: 02/10/2018 09:20 (80), 01/03/2020 14:49 (6), 02/03/2021 08:08 (2), 02/06/2023 10:06 (4)
Complete: 🔍
Cache ID: 216:17E:103

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

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