What’s Vulnerable › Vulnerabilities
CVE-2021-1619: Cisco IOS XE Software NETCONF and RESTCONF Authentication Bypass Vulnerability
- Severity: critical (CVSS 9.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.8% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2021-09-23 · updated 2026-06-17
- Weakness: CWE-824
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 products
- Cisco IOS XE: 16.3.1, 16.3.1a, 16.3.2, 16.3.3, 16.3.4, 16.3.5 (+113)
- Cisco IOS XE SD-WAN Software: all versions
- Cisco Ios Xe Sd-Wan 16.10.1 When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.1 When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.1 When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.1 When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.2 When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.2 When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.2 When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.2 When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.3 When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3 When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3 When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3 When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.3A When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3A When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3A When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3A When Installed On Cloud Services Router 1000V: series
- Cisco Ios Xe Sd-Wan 16.10.3A When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.3B When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3B When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3B When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.3B When Installed On Cloud Services Router 1000V: series
- Cisco Ios Xe Sd-Wan 16.10.3B When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.4 When Installed On 1000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.4 When Installed On 4000 Series Integrated Services: routers
- Cisco Ios Xe Sd-Wan 16.10.4 When Installed On Asr 1000 Series Aggregation Services: routers
- Cisco Ios Xe Sd-Wan 16.10.4 When Installed On Cloud Services Router 1000V: series
- Cisco Ios Xe Sd-Wan 16.10.4 When Installed On Integrated Services Virtual: router
- Cisco Ios Xe Sd-Wan 16.10.5 When Installed On 1000 Series Integrated Services: routers
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-aaa-Yx47ZT8Q
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-aaa-Yx47ZT8Q
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