VDB-58811 · CVE-2011-3277 · BID 49822

Cisco IOS up to 12.4 denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in Cisco IOS up to 12.4 (Router Operating System) and classified as critical. This issue affects an unknown code. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The program does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

Unspecified vulnerability in the NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload) by sending crafted H.323 packets to TCP port 1720, aka Bug ID CSCth11006.

The weakness was released 10/03/2011 with Cisco (Website). It is possible to read the advisory at cisco.com. The identification of this vulnerability is CVE-2011-3277 since 08/29/2011. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/23/2021). The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 56318 (Cisco IOS Software Network Address Translation Vulnerabilities (cisco-sa-20110928-nat)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CISCO. The commercial vulnerability scanner Qualys is able to test this issue with plugin 43218 (Cisco IOS Software Network Address Translation Vulnerabilities (cisco-sa-20110928-nat)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (56318). Entries connected to this vulnerability are available at 58814, 58813, 58812 and 58810.






  • commercial


  • end of life (version)

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.5
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Denial of service
CWE: CWE-404
ATT&CK: T1499

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 56318
Nessus Name: Cisco IOS Software Network Address Translation Vulnerabilities (cisco-sa-20110928-nat)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍


08/29/2011 🔍
09/28/2011 +30 days 🔍
09/28/2011 +0 days 🔍
10/02/2011 +4 days 🔍
10/03/2011 +1 days 🔍
10/03/2011 +0 days 🔍
03/23/2015 +1267 days 🔍
11/23/2021 +2437 days 🔍


Vendor: cisco.com

Advisory: cisco.com
Organization: Cisco
Status: Not defined
Confirmation: 🔍

CVE: CVE-2011-3277 (🔍)
Vulnerability Center: 33374 - [cisco-sa-20110928-nat] Cisco IOS Remote DoS Vulnerability via Crafted H.323 Packets, Medium
SecurityFocus: 49822 - Cisco IOS Network Address Translation Multiple Denial of Service Vulnerabilities

See also: 🔍


Created: 03/23/2015 04:50 PM
Updated: 11/23/2021 07:19 AM
Changes: 03/23/2015 04:50 PM (53), 04/07/2017 06:26 PM (12), 11/23/2021 07:19 AM (2)
Complete: 🔍


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