Cisco IOS XE Software IP Service Level Agreements Denial of Service Vulnerability

published 2020-09-24 6y ago modified 2026-06-17 4mo ago also EUVD-2020-24693

cvss: 8.6; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits: 0; none known

A vulnerability in the IP Service Level Agreement (SLA) responder feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the IP SLA responder to reuse an existing port, resulting in a denial of service (DoS) condition. The vulnerability exists because the IP SLA responder could consume a port that could be used by another feature. An attacker could exploit this vulnerability by sending specific IP SLA control packets to the IP SLA responder on an affected device. The control packets must include the port number that could be used by another configured feature. A successful exploit could allow the attacker to cause an in-use port to be consumed by the IP SLA responder, impacting the feature that was using the port and resulting in a DoS condition.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: last yr. (2024-11-13)

Exploit prediction

1.28% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	8.6	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:N/A:P

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-371 State Issues

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-ipsla-jw2DJmSv
vendor-advisory

Sources

CVE List CVE-2020-3422
NVD CVE-2020-3422

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