CVE-2017-12231: Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability

Reference page built from the source records below, each shown as its source publishes it. Dataset version ref-bb44b501aac3, updated 2026-11-02T23:39:54.475Z.

CISA Known Exploited Vulnerabilities

Name: Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability
Vendor: Cisco
Product: IOS software
Added to the catalog: 2022-03-03
Due date for US federal agencies: 2022-03-24
Weaknesses: CWE-399
Catalog version: 2026.10.30

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.

Required action (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

https://nvd.nist.gov/vuln/detail/CVE-2017-12231

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status: Analyzed
Published: 2017-09-29T01:34:48.747
Last modified: 2026-06-17T01:02:55.660
Weaknesses: CWE-399, NVD-CWE-noinfo

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.

Metric	Score	Severity	Vector	Scored by
CVSS 3.1	7.5	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	[email protected] (Primary)
CVSS 3.1	7.5	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)
CVSS 2.0	7.8	HIGH	AV:N/AC:L/Au:N/C:N/I:N/A:C	[email protected] (Primary)

References

http://www.securityfocus.com/bid/101039 (Broken Link, Third Party Advisory, VDB Entry)
http://www.securitytracker.com/id/1039449 (Broken Link, Third Party Advisory, VDB Entry)
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-nat (Vendor Advisory)
http://www.securityfocus.com/bid/101039 (Broken Link, Third Party Advisory, VDB Entry)
http://www.securitytracker.com/id/1039449 (Broken Link, Third Party Advisory, VDB Entry)
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-nat (Vendor Advisory)
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12231 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:35.381Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2017-12231

CVE record

Assigner: cisco
State: PUBLISHED
Published: 2017-09-28T07:00:00.000Z
Updated: 2026-01-14T14:53:00.751Z
Problem types: CWE-399

References

Read on 2026-11-03T00:34:48.739Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2017/12xxx/CVE-2017-12231.json

Sources and licences

CISA
Source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30, CC0 1.0. Use of this data does not imply endorsement by CISA or DHS.
CC0 1.0 Universal
National Vulnerability Database (NIST)
This product uses the NVD API but is not endorsed or certified by the NVD.
NVD API Terms of Use (NIST publications in the public domain, 17 U.S.C. 105)
CVE Program, The MITRE Corporation
Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation. CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
CVE Program Terms of Use ("CVE Usage" licence)

Cite this page

Dragons Eye Ransomware Tracker, "CVE-2017-12231: Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability",
entity page, dataset version ref-bb44b501aac3, updated 2026-11-02T23:39:54.475Z,
https://ransomware-tracker.com/cve/CVE-2017-12231 (accessed 2026-11-03).
Underlying source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30.
Underlying source: National Vulnerability Database (NIST), CVE API 2.0, record last modified 2026-06-17T01:02:55.660.
Underlying source: CVE List (CVE Program, The MITRE Corporation), record updated 2026-01-14T14:53:00.751Z.

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