Products & Services
Support

Product Categories


Popular Downloads


Manage Software

How to Buy

For Home

Linksys Products Store
Linksys is now part of Belkin
Products for everyone

All Ordering Options

Training & Events Partners
Guest

Vulnerability Alert

Cisco IOS Software Reverse SSH Vulnerability

 
Threat Type:
IntelliShield ID:25365
Version:1
First Published:2012 March 28 16:17 GMT
Last Published:2012 March 28 16:17 GMT
Port: 22
CVE:CVE-2012-0386
Urgency:Unlikely Use
Credibility:Confirmed
Severity:Mild Damage
CVSS Base:7.8 CVSS Calculator
CVSS Version 2.0
CVSS Temporal:6.4
Related Resources:
View related Security Advisory
 
 
Version Summary:

Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition. Updates are available.

 
 
Description

Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.

The vulnerability is due to errors in the reverse SSH feature. An unauthenticated, remote attacker could exploit this vulnerability to cause the targeted device to reset, resulting in a DoS condition.

Cisco confirmed the vulnerability in a security advisory and released updated software.

 
Warning Indicators
Cisco has published a list of affected Cisco IOS Software releases in the security advisory. The Vendor Announcements section of this alert contains a link to the advisory.
 
IntelliShield Analysis

To exploit this vulnerability, the attacker would need to attempt to authenticate to the targeted system using a crafted login.  To achieve this objective, the attacker may need access to trusted, internal network resources.  This access requirement reduces the exposure of this vulnerability.

Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.

 
Vendor Announcements

Cisco has released a security advisory for Cisco bug ID CSCtr49064 at the following link: cisco-sa-20120328-ssh

 
Impact

An unauthenticated, remote attacker could exploit this vulnerability to cause a targeted device to reset.  Sustained attacks could result in a DoS condition.

 
Technical Information

The vulnerability is due to errors in the SSH version 2 reverse SSH feature. This feature is often used for dial-out modems.

An unauthenticated, remote attacker could exploit this vulnerability by attempting to access the device via a reverse SSH login with a crafted username. Processing the crafted username could cause the device to reset.  Sustained attacks could result in a DoS condition.

 
Safeguards

Administrators are advised to apply the appropriate updates.

Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected devices.

Administrators may consider enabling SSH version 1 on affected devices. Customers should be aware of the limitations and vulnerabilities of SSH version 1 protocol before applying this workaround.

Administrators may consider using a vty access class to allow only trusted systems to access SSH on the affected devices.

Administrators may consider using the Control Plane Policing (CoPP) feature to allow only trusted systems reach the route processor (RP) on the affected devices.

Administrators are advised to allow only trusted users to have network access.

Administrators may consider disabling the SSH server feature on trusted networks.

Administrators are advised to monitor affected systems.

 
Patches/Software

Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco. Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via e-mail at tac@cisco.com.

 
Alert History
 

Initial Release



Product Sets
 
The security vulnerability applies to the following combinations of products.

Primary Products:
CiscoIOS 12.2EY 12.2(58)EY, 12.2(58)EY1 | 12.4GC Base, 12.4(22)GC1, 12.4(22)GC1a, 12.4(24)GC1, 12.4(24)GC3, 12.4(24)GC3a, 12.4(24)GC4 | 12.4JA 12.4(10b)JA, 12.4(10b)JA1, 12.4(10b)JA2, 12.4(10b)JA3, 12.4(10b)JA4, 12.4(13d)JA, 12.4(16b)JA, 12.4(16b)JA1, 12.4(18a)JA, 12.4(18a)JA1, 12.4(18a)JA2, 12.4(18a)JA3, 12.4(21a)JA, 12.4(21a)JA1, 12.4(21a)JA2, 12.4(23c)JA, 12.4(23c)JA1, 12.4(23c)JA2, 12.4(23c)JA3, 12.4(25d)JA, 12.4(25d)JA1 | 12.4JAX 12.4(25d)JAX | 12.4JDA Base, 12.4(10b)JDA, 12.4(10b)JDA1, 12.4(10b)JDA2, 12.4(10b)JDA3 | 12.4JDC Base, 12.4(10b)JDC | 12.4JDD Base, 12.4(10b)JDD | 12.4JDE Base, 12.4(10b)JDE | 12.4JHA Base, 12.4(21a)JHA | 12.4JHB Base, 12.4(21a)JHB, 12.4(21a)JHB1 | 12.4JHC 12.4(21a)JHC, Base | 12.4JX 12.4(10b)JX, 12.4(21a)JX | 12.4JY 12.4(21a)JY | 12.4JZ Base, 12.4(21a)JZ | 12.4MD 12.4(15)MD, 12.4(15)MD1, 12.4(15)MD2, 12.4(15)MD3, 12.4(15)MD4, 12.4(15)MD5, 12.4(22)MD, 12.4(22)MD1, 12.4(22)MD2, 12.4(24)MD, 12.4(24)MD1, 12.4(24)MD2, 12.4(24)MD3, 12.4(24)MD4, 12.4(24)MD5, 12.4(24)MD6 | 12.4MDA Base, 12.4(22)MDA, 12.4(22)MDA1, 12.4(22)MDA2, 12.4(22)MDA3, 12.4(22)MDA4, 12.4(22)MDA5, 12.4(22)MDA6, 12.4(24)MDA, 12.4(24)MDA1, 12.4(24)MDA10, 12.4(24)MDA2, 12.4(24)MDA3, 12.4(24)MDA4, 12.4(24)MDA5, 12.4(24)MDA6, 12.4(24)MDA7, 12.4(24)MDA8, 12.4(24)MDA9 | 12.4MDB Base, 12.4(24)MDB, 12.4(24)MDB1, 12.4(24)MDB2, 12.4(24)MDB3, 12.4(24)MDB4, 12.4(24)MDB5 | 12.4MR 12.4(16)MR2, 12.4(19)MR, 12.4(19)MR1, 12.4(19)MR2, 12.4(20)MR, 12.4(20)MR2 | 12.4MRA Base, 12.4(20)MRA, 12.4(20)MRA1 | 12.4MRB Base, 12.4(20)MRB, 12.4(20)MRB1 | 12.4T 12.4(15)T10, 12.4(15)T11, 12.4(15)T12, 12.4(15)T13, 12.4(15)T13b, 12.4(15)T14, 12.4(15)T15, 12.4(15)T9, 12.4(20)T, 12.4(20)T1, 12.4(20)T2, 12.4(20)T3, 12.4(20)T4, 12.4(20)T5, 12.4(20)T5a, 12.4(20)T6, 12.4(22)T4, 12.4(22)T5, 12.4(24)T, 12.4(24)T1, 12.4(24)T2, 12.4(24)T3, 12.4(24)T3c, 12.4(24)T3e, 12.4(24)T3f, 12.4(24)T35c, 12.4(24)T4, 12.4(24)T4a, 12.4(24)T4b, 12.4(24)T4c, 12.4(24)T5 | 12.4XQ Base, 12.4(15)XQ, 12.4(15)XQ1, 12.4(15)XQ2, 12.4(15)XQ2a, 12.4(15)XQ2b, 12.4(15)XQ2c, 12.4(15)XQ2d, 12.4(15)XQ3, 12.4(15)XQ4, 12.4(15)XQ5, 12.4(15)XQ6, 12.4(15)XQ7, 12.4(15)XQ8 | 12.4XR Base, 12.4(15)XR, 12.4(15)XR1, 12.4(15)XR10, 12.4(15)XR2, 12.4(15)XR3, 12.4(15)XR4, 12.4(15)XR5, 12.4(15)XR6, 12.4(15)XR7, 12.4(15)XR8, 12.4(15)XR9, 12.4(22)XR, 12.4(22)XR1, 12.4(22)XR10, 12.4(22)XR11, 12.4(22)XR12, 12.4(22)XR2, 12.4(22)XR3, 12.4(22)XR4, 12.4(22)XR5, 12.4(22)XR6, 12.4(22)XR7, 12.4(22)XR8, 12.4(22)XR9 | 12.4XZ Base, 12.4(15)XZ, 12.4(15)XZ1, 12.4(15)XZ2 | 12.4YA Base, 12.4(20)YA, 12.4(20)YA1, 12.4(20)YA2, 12.4(20)YA3 | 12.4YB Base, 12.4(22)YB, 12.4(22)YB1, 12.4(22)YB4, 12.4(22)YB5, 12.4(22)YB6, 12.4(22)YB7, 12.4(22)YB8 | 12.4YD Base, 12.4(22)YD, 12.4(22)YD1, 12.4(22)YD2, 12.4(22)YD3, 12.4(22)YD4 | 12.4YE Base, 12.4(22)YE, 12.4(22)YE1, 12.4(22)YE2, 12.4(22)YE3, 12.4(22)YE4, 12.4(22)YE5, 12.4(22)YE6, 12.4(24)YE, 12.4(24)YE1, 12.4(24)YE2, 12.4(24)YE3, 12.4(24)YE3a, 12.4(24)YE3b, 12.4(24)YE3c, 12.4(24)YE3d, 12.4(24)YE4, 12.4(24)YE5, 12.4(24)YE6, 12.4(24)YE7 | 12.4YG Base, 12.4(24)YG1, 12.4(24)YG2, 12.4(24)YG3 | 15.0M Base, 15.0(1)M, 15.0(1)M1, 15.0(1)M2, 15.0(1)M3, 15.0(1)M4, 15.0(1)M5, 15.0(1)M6, 15.0(1)M6a | 15.0MR Base, 15.0(1)MR, 15.0(2)MR | 15.0S Base, 15.0(1)S, 15.0(1)S1, 15.0(1)S2, 15.0(1)S3, 15.0(1)S3a, 15.0(1)S4, 15.0(1)S4a | 15.0SE 15.0(1)SE | 15.0XA Base, 15.0(1)XA, 15.0(1)XA1, 15.0(1)XA2, 15.0(1)XA3, 15.0(1)XA4 | 15.1EY 15.1(2)EY1 | 15.1GC Base, 15.1(2)GC, 15.1(2)GC1 | 15.1M 15.1(4)M, 15.1(4)M0a, 15.1(4)M0b, 15.1(4)M1 | 15.1MR 15.1(1)MR, 15.1(1)MR1, 15.1(1)MR2 | 15.1S Base, 15.1(1)S, 15.1(1)S1, 15.1(1)S2, 15.1(2)S, 15.1(2)S1, 15.1(2)S2, 15.1(3)S, 15.1(3)S0a, 15.1(3)S1 | 15.1SNG 15.1(2)SNG, 15.1(2)SNG1 | 15.1T Base, 15.1(1)T, 15.1(1)T1, 15.1(1)T2, 15.1(1)T3, 15.1(2)T, 15.1(2)T0a, 15.1(2)T1, 15.1(2)T10, 15.1(2)T2, 15.1(2)T2a, 15.1(2)T3, 15.1(2)T4, 15.1(3)T, 15.1(3)T1, 15.1(3)T2 | 15.1XB Base, 15.1(1)XB, 15.1(1)XB1, 15.1(1)XB2, 15.1(1)XB3, 15.1(4)XB4, 15.1(4)XB5 | 15.2GC 15.2(1)GC | 15.2T 15.2(1)T, 15.2(1)T1
CiscoCisco IOS XE Software 2.3 .0, .0t, .1t, .2 | 2.4 .0, .1 | 2.5 .0 | 2.6 .0, .1, .2 | 3.1S .0, .1, .2, .3 | 3.2S .0, .1, .2 | 3.3S .0, .1, .2 | 3.4S .0, .1 | 3.5S Base

Associated Products:
CiscoIOS 12.2EY | 12.2SE 12.2(58)SE2 | 12.4 12.4(13e), 12.4(13f), 12.4(16b), 12.4(17a), 12.4(17b), 12.4(18), 12.4(18a), 12.4(18b), 12.4(18c), 12.4(18d), 12.4(18e), 12.4(19), 12.4(21), 12.4(21a), 12.4(23), 12.4(23a), 12.4(23b), 12.4(23c), 12.4(23d), 12.4(23e), 12.4(25), 12.4(25a), 12.4(25b), 12.4(25c), 12.4(25d), 12.4(25e) | 12.4GC | 12.4JA | 12.4JAX | 12.4JDA | 12.4JDC | 12.4JDD | 12.4JDE | 12.4JHA | 12.4JHB | 12.4JHC | 12.4JX | 12.4JY 12.4(23c)JY | 12.4JZ 12.4(23c)JZ | 12.4M 12.4(21a)M1, 12.4(23b)M1 | 12.4MD | 12.4MDA | 12.4MDB | 12.4MR | 12.4MRA | 12.4MRB | 12.4T 12.4(22)T, 12.4(22)T1, 12.4(22)T2, 12.4(22)T3 | 12.4XQ | 12.4XR | 12.4XZ | 12.4YA | 12.4YB | 12.4YD | 12.4YE | 12.4YG | 15.0M | 15.0MR | 15.0S | 15.0SE | 15.0XA 15.0(1)XA5 | 15.1EY 15.1(2)EY | 15.1GC | 15.1M | 15.1MR | 15.1S | 15.1SNG | 15.1T | 15.1XB | 15.2GC | 15.2T
CiscoCisco IOS XE Software 2.6




Alerts and bulletins on the Cisco Security Intelligence Operations Portal are highlighted by analysts in the Cisco Threat Operations Center and represent a subset of the comprehensive content that is available through Cisco Security IntelliShield Alert Manager Service. This customizable threat and vulnerability alert service provides security staff with access to timely, accurate, and credible information about threats and vulnerabilities that may affect their environment.


LEGAL DISCLAIMER
The urgency and severity ratings of this alert are not tailored to individual users; users may value alerts differently based upon their network configurations and circumstances. THE ALERT, AND INFORMATION CONTAINED THEREIN, ARE PROVIDED ON AN "AS IS" BASIS AND DO NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE ALERT, AND INFORMATION CONTAINED THEREIN, OR MATERIALS LINKED FROM THE ALERT, IS AT YOUR OWN RISK. INFORMATION IN THIS ALERT AND ANY RELATED COMMUNICATIONS IS BASED ON OUR KNOWLEDGE AT THE TIME OF PUBLICATION AND IS SUBJECT TO CHANGE WITHOUT NOTICE. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE ALERTS AT ANY TIME.
Powered by  IntelliShield