MontaVista Software has released a changelog and updated software to address the Net-SNMP SNMP GET request extension table denial of service vulnerability.
Description
Net-SNMP contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
The vulnerability is due to improper handling of certain SNMP requests by the affected software. An unauthenticated, remote attacker could exploit this vulnerability by sending a crafted SNMP GET request to the targeted system. If successful, this action could terminate the affected software unexpectedly, resulting in a DoS condition on the targeted system.
Net-SNMP has confirmed this vulnerability. However, updated software is not available.
Warning Indicators
Net-SNMP version 5.7.1 is vulnerable. Other versions may also be affected.
IntelliShield Analysis
To exploit this vulnerability, the attacker would need to send crafted SNMP GET requests to the targeted system. Depending on the network configuration, the attacker would need access to trusted, internal networks. The attacker would also need read privileges for a MIB subtree.
Vendor Announcements
Net-SNMP has released a bug report at the following link: CVE-2012-2141
MontaVista Software has released a changelog for registered users on March 14, 2013, at the following link: MontaVista Security Fixes
An unauthenticated, remote attacker could exploit this vulnerability to terminate the affected software unexpectedly, resulting in a DoS condition on the targeted system.
Technical Information
The vulnerability is in the handle_nsExtendOutput2Table() function that is used by the affected software.
An unauthenticated, remote attacker could exploit this vulnerability by sending crafted SNMP GET requests for a nonexistent extension table entry. If successful, this action could allow the attacker to terminate the affected software unexpectedly, resulting 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 systems.
Administrators are advised to monitor affected systems.
Patches/Software
CentOS packages can be updated using the up2date or yum command.
MontaVista Software has released updated software for registered users at the following links:
Red Hat has released updated software for registered subscribers at the following link: Red Hat Network. Red Hat packages can be updated on Red Hat Enterprise Linux versions 5 and later using the yum tool.
Alert History
Version 4, January 8, 2013, 6:27 AM: Red Hat has released an additional security advisory and updated packages to address the Net-SNMP SNMP GET request extension table denial of service vulnerability.
Version 3, July 11, 2012, 8:07 AM: CentOS has released updated packages to address the Net-SNMP SNMP GET request extension table denial of service vulnerability.
Version 2, June 22, 2012, 3:27 PM: Red Hat has released a security advisory and packages to address the Net-SNMP SNMP GET request extension table denial of service vulnerability.
Version 1, April 27, 2011, 9:25 AM: Net-SNMP contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition. Updates are not available.
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