Citrix Access Gateway up to 8.0 ActiveX Control nsepa.ocx memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Citrix Access Gateway up to 8.0. Impacted is an unknown function of the file nsepa.ocx of the component ActiveX Control. The manipulation leads to memory corruption. This vulnerability is referenced as CVE-2011-2882. Furthermore, an exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Citrix Access Gateway up to 8.0 (Connectivity Software). It has been rated as very critical. This issue affects some unknown processing of the file nsepa.ocx of the component ActiveX Control. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Stack-based buffer overflow in 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 allows remote attackers to execute arbitrary code via crafted HTTP header data.

The weakness was published 07/21/2011 by Joshua J. Drake (Website). The advisory is shared at securityreason.com. The identification of this vulnerability is CVE-2011-2882. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/25/2025).

A public exploit has been developed by Metasploit in Ruby and been published 2 months after the advisory. The exploit is available at securityfocus.com. It is declared as highly functional. We expect the 0-day to have been worth approximately $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. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 12271.

The vulnerability is also documented in the databases at Exploit-DB (17762), Tenable (55653), SecurityFocus (BID 48676†) and Vulnerability Center (SBV-32418†). Similar entry is available at VDB-58086. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Highly functional
Author: Metasploit
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: 🔍

Saint ID: exploit_info/citrix_access_gateway_activex_nsepa
Saint Name: Citrix Access Gateway NESPA ActiveX Control

MetaSploit ID: citrix_gateway_actx.rb
MetaSploit Name: Citrix Gateway ActiveX Control Stack Based Buffer Overflow Vulnerability
MetaSploit File: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Upgrade: Access Gateway 8.1
TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

PaloAlto IPS: 🔍
Fortigate IPS: 🔍

Timelineinfo

07/14/2011 🔍
07/21/2011 +6 days 🔍
07/21/2011 +0 days 🔍
07/21/2011 +0 days 🔍
07/21/2011 +0 days 🔍
07/22/2011 +1 days 🔍
07/25/2011 +3 days 🔍
08/31/2011 +37 days 🔍
08/31/2011 +0 days 🔍
03/23/2015 +1300 days 🔍
05/25/2025 +3716 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: securityreason.com
Researcher: Joshua J. Drake
Status: Confirmed

CVE: CVE-2011-2882 (🔍)
GCVE (CVE): GCVE-0-2011-2882
GCVE (VulDB): GCVE-100-58085
SecurityFocus: 48676 - Citrix Access Gateway Plug-in ActiveX Control Multiple Code Execution Vulnerabilities
Vulnerability Center: 32418 - Citrix Access Gateway Enterprise Edition Remote Stack-Based Buffer Overflow Vulnerability, Medium

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

Entryinfo

Created: 03/23/2015 16:50
Updated: 05/25/2025 14:18
Changes: 03/23/2015 16:50 (68), 03/28/2017 10:34 (18), 11/15/2021 13:37 (2), 11/15/2021 13:43 (1), 05/25/2025 14:18 (14)
Complete: 🔍
Cache ID: 216:847:103

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