Denial of service in Cisco IOS XR Software

1) Input validation error

EUVDB-ID: #VU67389

Risk: Low

CVSSv4.0: 2.3 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2022-20849

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to the affected application does not properly handle an error condition in the Broadband Network Gateway PPP over Ethernet (PPPoE) feature. A remote attacker on the local network can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 6.8 - 7.5.0

Cisco ASR 9000 Series Aggregation Services Routers: All versions

Cisco IOS XRv 9000 Router: All versions

CPE2.3

• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.8:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.1:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.2.0:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.3:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.4:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.5.0:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:cisco_asr_9000_series_aggregation_services_routers:*:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:cisco_ios_xrv_9000_router:*:*:*:*:*:*:*:*

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-bng-Gmg5Gxt

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.