High 7.5Known exploited (CISA KEV)Published Sep 7, 2017

CVE-2017-6627A 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 syste…

Updated under an hour ago (2026-10-19 08:40 UTC)

Does this affect you?

It affects cisco ios and 1 other product. Add what you run to find out whether that includes you.

CISA lists it as known exploited since Mar 3, 2022; federal agencies had to remediate by Mar 24, 2022. Treat that date as your deadline.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for cisco ios

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-399
Known exploited: Added to CISA KEV Mar 3, 2022; federal remediation due Mar 24, 2022Apply updates per vendor instructions.
EPSS (exploitation in the next 30 days): 6.16% (percentile 93)
Assigned by: cisco
NVD analysis: Analyzed
Record last updated: Oct 21, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

cisco ios cisco:ios	15.1(2)gc; 15.1(2)gc1; 15.1(2)gc2; 15.1(4)gc; 15.1(4)gc1; 15.1(4)gc2; 15.2(1)gc; 15.2(1)gc1; and 27 more ranges	NVD
cisco ios_xe cisco:ios_xe	3.14.0s; 3.14.1s; 3.14.2s; 3.14.3s; 3.14.4s; 3.15.0s; 3.15.1cs; 3.15.1s; and 28 more ranges	NVD

References

http://www.securityfocus.com/bid/100644vdb-entry, x-refsource-bid, broken-link, third-party-advisory
http://www.securitytracker.com/id/1039289vdb-entry, x-refsource-sectrack, broken-link, third-party-advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170906-ios-udpx-refsource-confirm, mitigation, vendor-advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-6627us-government-resource

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.