Medium severity · published Mar 12, 2025
CVE-2025-20144
A vulnerability in the hybrid access control list (ACL) processing of IPv4 packets in Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass a configured…
5.8
CVSS
0.3%
EPSS
No
On KEV
Description
A vulnerability in the hybrid access control list (ACL) processing of IPv4 packets in Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass a configured ACL.
This vulnerability is due to incorrect handling of packets when a specific configuration of the hybrid ACL exists. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass a configured ACL on the affected device.
For more information, see the section of this advisory.
Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IX
Ios XR · Cisco
6.5.1; 6.5.2; 6.5.3; 6.5.92; 6.5.93; 6.6.1; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-20144
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-20144
Technical Description
https://blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/
Vendor Advisory
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ncs-hybridacl-crMZFfKQ
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