CVE-2021-1619

Cisco IOS XE Software NETCONF and RESTCONF Authentication Bypass Vulnerability

CRITICAL
9.1
CVSS Score
Published: September 23, 2021 at 02:30 AM UTC
Updated: June 17, 2026 at 03:32 AM UTC
146 products affected across 1 vendorIOS XeIOS Xe Sd WANIOS Xe Sd WAN 16.11.1f When Installed on 4000 Series Integrated Services

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Severity
CRITICAL9.1
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusUNDERGOING ANALYSIS
CWE
CWE-824CWE-908

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