CVE-2017-6627: Cisco IOS Software and Cisco IOS XE Software UDP Packet Processing Denial-of-Service Vulnerability

CISA Known Exploited Vulnerabilities

Name

Cisco IOS Software and Cisco IOS XE Software UDP Packet Processing Denial-of-Service Vulnerability

Vendor

Cisco

Product

IOS and IOS XE 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 UDP processing code of Cisco IOS and IOS XE could allow an unauthenticated, remote attacker to cause the input queue of an affected system to hold UDP packets, causing an interface queue wedge and 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-2017-6627

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

2017-09-07T21:29:00.660

Last modified

2026-06-17T01:22:40.730

Weaknesses

CWE-399, CWE-404

A vulnerability in the UDP processing code of Cisco IOS 15.1, 15.2, and 15.4 and IOS XE 3.14 through 3.18 could allow an unauthenticated, remote attacker to cause the input queue of an affected system to hold UDP packets, causing an interface queue wedge and a denial of service (DoS) condition. The vulnerability is due to Cisco IOS Software application changes that create UDP sockets and leave the sockets idle without closing them. An attacker could exploit this vulnerability by sending UDP packets with a destination port of 0 to an affected device. A successful exploit could allow the attacker to cause UDP packets to be held in the input interfaces queue, resulting in a DoS condition. The input interface queue will stop holding UDP packets when it receives 250 packets. Cisco Bug IDs: CSCup10024, CSCva55744, CSCva95506.

References

• http://www.securityfocus.com/bid/100644 (Broken Link, Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1039289 (Broken Link, Third Party Advisory, VDB Entry)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170906-ios-udp (Mitigation, Vendor Advisory)
• http://www.securityfocus.com/bid/100644 (Broken Link, Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1039289 (Broken Link, Third Party Advisory, VDB Entry)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170906-ios-udp (Mitigation, Vendor Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-6627 (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-2017-6627

CVE record

Assigner

cisco

State

PUBLISHED

Published

2017-09-07T21:00:00.000Z

Updated

2025-10-21T23:55:34.940Z

Problem types

CWE-399

A vulnerability in the UDP processing code of Cisco IOS 15.1, 15.2, and 15.4 and IOS XE 3.14 through 3.18 could allow an unauthenticated, remote attacker to cause the input queue of an affected system to hold UDP packets, causing an interface queue wedge and a denial of service (DoS) condition. The vulnerability is due to Cisco IOS Software application changes that create UDP sockets and leave the sockets idle without closing them. An attacker could exploit this vulnerability by sending UDP packets with a destination port of 0 to an affected device. A successful exploit could allow the attacker to cause UDP packets to be held in the input interfaces queue, resulting in a DoS condition. The input interface queue will stop holding UDP packets when it receives 250 packets. Cisco Bug IDs: CSCup10024, CSCva55744, CSCva95506.

References

• 100644
• 1039289
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170906-ios-udp

Read on 2026-11-03T00:35:20.099Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2017/6xxx/CVE-2017-6627.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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