Cisco · IOS software
CVE-2017-12231
Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability
What it is
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.
CISA: A vulnerability in the implementation of Network Address Translation (NAT) functionality in Cisco IOS could allow an unauthenticated, remote attacker to cause a denial of service.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: March 24, 2022
More exploited flaws from Cisco
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Mar 3, 2022 | SNMP Remote Code Execution | IOS software | High 8.8 | 7.3% |
| Mar 3, 2022 | Integrated Services Module for VPN Denial-of-Service | IOS Software | High 7.5 | 7.1% |
| Mar 3, 2022 | Resource Management Errors | IOS Software | Medium 6.3 | 4.1% |
| Mar 3, 2022 | Denial-of-Service | IOS Software | Medium 6.8 | 4.9% |
| Mar 3, 2022 | Denial-of-Service | IOS Software | Medium 6.8 | 4.9% |
| Mar 3, 2022 | for Cisco Integrated Services Routers Denial-of-Service | IOS software | Medium 6.5 | 2.2% |
| Mar 3, 2022 | Common Industrial Protocol Request Denial-of-Service | IOS software | High 7.5 | 7.1% |
| Mar 3, 2022 | Common Industrial Protocol Request Denial-of-Service | IOS software | High 7.5 | 7.1% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.