Denial of service in Cisco IOS XR software segment routing feature

1) Input validation error

EUVDB-ID: #VU97201

Risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2024-20406

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 insufficient validation of ingress IS-IS packets in the segment routing feature for the Intermediate System-to-Intermediate System (IS-IS) protocol. A remote attacker on the local network can pass specially crafted packets to the device and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 7.0 - 7.11.1

CPE2.3

• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.0.90:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.11.1:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.2.12:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.3.15:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.4.2:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.5.4:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.6.3:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.7.21:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.8.2:*:*:*:*:*:*:*
• cpe:2.3:o:cisco_systems:cisco_ios_xr:7.9.21:*:*:*:*:*:*:*

External links

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-xehpbVNe
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwi39542

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.