Trustwave ModSecurity up to 2.7.6 Chunked HTTP Transfer apache2/modsecurity.c modsecurity_tx_init Trailing Header access control

CVSS Meta Temp Score
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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Trustwave ModSecurity up to 2.7.6. This vulnerability affects the function modsecurity_tx_init of the file apache2/modsecurity.c of the component Chunked HTTP Transfer Handler. Performing a manipulation as part of Trailing Header results in access control. This vulnerability is identified as CVE-2013-5704. Additionally, an exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Trustwave ModSecurity up to 2.7.6. It has been classified as critical. This affects the function modsecurity_tx_init of the file apache2/modsecurity.c of the component Chunked HTTP Transfer Handler. The manipulation as part of a Trailing Header leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on integrity. The summary by CVE is:

The mod_headers module in the Apache HTTP Server 2.2.22 allows remote attackers to bypass "RequestHeader unset" directives by placing a header in the trailer portion of data sent with chunked transfer coding. NOTE: the vendor states "this is not a security issue in httpd as such."

The weakness was released 03/31/2014 by Martin Holst Swende as Chunked HTTP transfer encoding as confirmed posting (Blog). The advisory is shared at martin.swende.se. The public release was coordinated with Trustwave. This vulnerability is uniquely identified as CVE-2013-5704 since 09/05/2013. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details and a public exploit are known. MITRE ATT&CK project uses the attack technique T1068 for this issue.

A public exploit has been developed by Martin Holst Swende in HTTP POST Request and been published immediately after the advisory. The exploit is shared for download at martin.swende.se. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 4 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 81401 (IBM WebSphere Application Server 8.0 < Fix Pack 10 Multiple Vulnerabilities (POODLE)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Web Servers and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350219 (Amazon Linux Security Advisory for httpd24: ALAS-2015-483). The code used by the exploit is:

POST /test.php HTTP/1.1
Host: localhost.me
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:23.0) Gecko/20100101 Firefox/23.0
Content-Type: application/x-www-form-urlencoded
Transfer-Encoding: chunked
Removeme: willbegone

3
x=a
0
X-user-id: foobar
Removeme: noyouwont

Upgrading eliminates this vulnerability. Applying the patch 2.7.6 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (92235), Tenable (81401), SecurityFocus (BID 66550†) and Secunia (SA57444†). Entries connected to this vulnerability are available at VDB-12742, VDB-67790, VDB-68435 and VDB-68668. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.3
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Martin Holst Swende
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 81401
Nessus Name: IBM WebSphere Application Server 8.0 < Fix Pack 10 Multiple Vulnerabilities (POODLE)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 11745
OpenVAS Name: Ubuntu Update for apache2 USN-2523-1
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: 🔍
Exploit Delay Time: 🔍

Patch: 2.7.6

Timelineinfo

09/05/2013 🔍
09/05/2013 +0 days 🔍
09/05/2013 +0 days 🔍
09/09/2013 +4 days 🔍
03/31/2014 +203 days 🔍
03/31/2014 +0 days 🔍
03/31/2014 +0 days 🔍
04/01/2014 +1 days 🔍
04/01/2014 +0 days 🔍
04/15/2014 +14 days 🔍
02/18/2015 +309 days 🔍
04/30/2019 +1532 days 🔍

Sourcesinfo

Advisory: Chunked HTTP transfer encoding
Researcher: Martin Holst Swende
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2013-5704 (🔍)
GCVE (CVE): GCVE-0-2013-5704
GCVE (VulDB): GCVE-100-12741

OVAL: 🔍

X-Force: 92235 - Apache HTTP Server mod_headers security bypass, Medium Risk
SecurityFocus: 66550 - ModSecurity 'mod_headers' module Security Bypass Vulnerability
Secunia: 57444 - ModSecurity HTTP Requests Chunked Encoding Security Bypass Vulnerability, Moderately Critical

scip Labs: https://www.scip.ch/en/?labs.20130913
See also: 🔍

Entryinfo

Created: 04/01/2014 16:27
Updated: 04/30/2019 21:50
Changes: 04/01/2014 16:27 (95), 04/30/2019 21:50 (5)
Complete: 🔍
Cache ID: 216:EAF:103

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