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
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.
为什么是这个 VPI(可解释·实验性)
VPI 计算依据
| 影响度 | 75.00 |
| 利用信号(KEV 收录) | ×1.50 |
| VPI | 100.00 |
VPI 公式 vpi-v1
必要措施
Apply updates per vendor instructions.
| 来源 | CVSS 版本 | 基础评分 | 严重程度 | 向量字符串 | 评估日期 |
|---|---|---|---|---|---|
| NVDNIST | 3.1 | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | 2026. 04. 20. |
| NVDNIST | 2.0 | 7.8 |
| AV:N/AC:L/Au:N/C:N/I:N/A:C |
| 2026. 04. 20. |