Cisco IOS XE Software NETCONF and RESTCONF Authentication Bypass Vulnerability

published 2021-09-23 5y ago modified 2026-06-17 4mo ago also EUVD-2021-7086

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.8%; EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits: 0; none known

A vulnerability in the authentication, authorization, and accounting (AAA) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass NETCONF or RESTCONF authentication and do either of the following: Install, manipulate, or delete the configuration of an affected device Cause memory corruption that results in a denial of service (DoS) on an affected device This vulnerability is due to an uninitialized variable. An attacker could exploit this vulnerability by sending a series of NETCONF or RESTCONF requests to an affected device. A successful exploit could allow the attacker to use NETCONF or RESTCONF to install, manipulate, or delete the configuration of a network device or to corrupt memory on the device, resulting a DoS.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 2y ago (2024-11-07)

Exploit prediction

1.76% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	9.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
NVD	2.0	6.4	AV:N/AC:L/Au:N/C:N/I:P/A:P

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-824 Access of Uninitialized Pointer
CWE-908 Use of Uninitialized Resource

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-aaa-Yx47ZT8Q
vendor-advisory

Sources

CVE List CVE-2021-1619
NVD CVE-2021-1619

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