#VU105698 Buffer overflow in Cisco IOS XR - CVE-2025-20115

Vulnerability identifier: #VU105698

Vulnerability risk: High

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-20115

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XR
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

Description

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

The vulnerability exists due to a boundary error in confederation implementation for the Border Gateway Protocol (BGP). A remote attacker can send a specially crafted BGP update message, trigger memory corruption and cause a denial of service condition on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 7.11, 24.1, 24.2, 24.3

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External links
https://blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-bgp-dos-O7stePhX

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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