CVE-2017-12231
Cisco IOS
Published 29 Sept 2017 · updated 17 Jun 2026 · Analyzed
Exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on 3 Mar 2022, with a remediation deadline of 24 Mar 2022 for US federal agencies.
Required action: Apply updates per vendor instructions.
Description
A vulnerability in the implementation of Network Address Translation (NAT) functionality in Cisco IOS 12.4 through 15.6 could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to the improper translation of H.323 messages that use the Registration, Admission, and Status (RAS) protocol and are sent to an affected device via IPv4 packets. An attacker could exploit this vulnerability by sending a crafted H.323 RAS packet through an affected device. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition. This vulnerability affects Cisco devices that are configured to use an application layer gateway with NAT (NAT ALG) for H.323 RAS messages. By default, a NAT ALG is enabled for H.323 RAS messages. Cisco Bug IDs: CSCvc57217.
References
- www.securityfocus.com/bid/101039 · Broken Link, Third Party Advisory, VDB Entry
- www.securitytracker.com/id/1039449 · Broken Link, Third Party Advisory, VDB Entry
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-nat · Vendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12231 · US Government Resource