Cisco IOS XE Software RESTCONF and NETCONF-YANG Access Control List Denial of Service Vulnerability

published 2020-09-24 6y ago modified 2026-06-17 4mo ago also EUVD-2020-24678

cvss: 8.6; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.5%; EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits: 0; none known

A vulnerability in the RESTCONF and NETCONF-YANG access control list (ACL) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of the ACL that is tied to the RESTCONF or NETCONF-YANG feature. An attacker could exploit this vulnerability by accessing the device using RESTCONF or NETCONF-YANG. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

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CISA SSVC

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

Exploit prediction

1.51% chance of exploitation in the next 30 days, higher than 74% 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	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	2.0	7.1	AV:N/AC:M/Au:N/C:N/I:N/A:C

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-476 NULL Pointer Dereference

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-confacl-HbPtfSuO
vendor-advisory

Sources

CVE List CVE-2020-3407
NVD CVE-2020-3407

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