Citrix Access Gateway up to 8.0 ActiveX Control nsepa.ocx input validation

CVSS Meta Temp Score
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CTI Interest Score
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9.0$0-$5k0.00

A vulnerability classified as critical has been found in Citrix Access Gateway up to 8.0 (Connectivity Software). Affected is an unknown function of the file nsepa.ocx of the component ActiveX Control. 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. CVE summarizes:

The NSEPA.NsepaCtrl.1 ActiveX control in nsepa.ocx in Citrix Access Gateway Enterprise Edition 8.1 before 8.1-67.7, 9.0 before 9.0-70.5, and 9.1 before 9.1-96.4 attempts to validate signed DLLs by checking the certificate subject, not the signature, which allows man-in-the-middle attackers to execute arbitrary code via HTTP header data referencing a DLL that was signed with a crafted certificate.

The weakness was released 07/21/2011 by Joshua J. Drake (Website). The advisory is available at labs.idefense.com. This vulnerability is traded as CVE-2011-2883. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details and a public exploit are known.

A public exploit has been developed in Ruby. The exploit is shared for download at securityfocus.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 55653 (Citrix Access Gateway Plug-in for Windows ActiveX Control Multiple Vulnerabilities (CTX129902)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows.

Upgrading to version 8.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (55653). Entry connected to this vulnerability is available at 58085.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.0

VulDB Base Score: 10.0
VulDB Temp Score: 9.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 55653
Nessus Name: Citrix Access Gateway Plug-in for Windows ActiveX Control Multiple Vulnerabilities (CTX129902)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Access Gateway 8.1
McAfee IPS: 🔍
McAfee IPS Version: 🔍

Timelineinfo

07/14/2011 🔍
07/14/2011 +0 days 🔍
07/21/2011 +6 days 🔍
07/21/2011 +0 days 🔍
07/21/2011 +0 days 🔍
07/25/2011 +4 days 🔍
03/23/2015 +1337 days 🔍
11/15/2021 +2429 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: labs.idefense.com⛔
Researcher: Joshua J. Drake
Status: Not defined

CVE: CVE-2011-2883 (🔍)
Vulnerability Center: 32419 - Citrix Access Gateway Enterprise Edition Remote Code Execution via Crafted DLL Certificate, Medium
SecurityFocus: 48676 - Citrix Access Gateway Plug-in ActiveX Control Multiple Code Execution Vulnerabilities

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 03/23/2015 16:50
Updated: 11/15/2021 13:56
Changes: 03/23/2015 16:50 (57), 03/28/2017 10:34 (14), 11/15/2021 13:49 (3), 11/15/2021 13:56 (2)
Complete: 🔍

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