What is the CVSS score of CVE-2017-12231?

CVE-2017-12231 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 6.8%.

Is CVE-2017-12231 being actively exploited?

Yes, CVE-2017-12231 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, confirming active in-the-wild exploitation. Immediate patching is required.

Cisco CVE-2017-12231

HIGH

Resource Management Errors (CWE-399)

2017-09-29 psirt@cisco.com

Cisco Denial Of Service Apple

7.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Added to CISA KEV

Apr 21, 2026 - 15:31 CISA

CVE Published

Sep 29, 2017 - 01:34 cve.org

HIGH 7.5

DescriptionCVE.org

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.

AnalysisAI

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. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Actively exploited in the wild (cisa kev) and no vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-399. 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. Affected products include: Cisco Ios. Version information: through 15.6.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.