CVE-2025-20159
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk22th percentile - higher than 22% of all known CVEs
Summary
A vulnerability in the management interface access control list (ACL) processing feature in Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass configured ACLs for the SSH, NetConf, and gRPC features. This occurs because management interface ACLs are not supported on Packet I/O infrastructure platforms for Linux-handled features.
Risk Assessment
An attacker could bypass an ingress ACL on the management interface and reach management services, potentially leading to unauthorized access to network infrastructure.
Recommendation
Apply the Cisco IOS XR Software updates containing the fix as soon as possible and consider additional access controls on devices exposing SSH, NetConf, and gRPC.
Other vulnerabilities in Cisco IOS XR Software
See all- CVE-2017-6731High
A vulnerability in Multicast Source Discovery Protocol (MSDP) ingress packet processing for Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the MSDP session to be unexpectedly reset, leading to a short denial of service (DoS) condition. The MSDP session will restart within a few seconds.
- CVE-2017-6728High
A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary code at the root privilege level on an affected system, due to Incorrect Permissions.
- CVE-2016-9205High
A vulnerability in the HTTP 2.0 request handling code of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the Event Management Service daemon (emsd) to crash, resulting in a denial of service (DoS) condition.
- CVE-2020-3569HighActively exploited
Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to immediately crash the IGMP process or cause memory exhaustion and eventual crash. This is due to incorrect handling of IGMP packets.
- CVE-2020-3566HighActively exploited
A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to exhaust process memory of an affected device. This is due to insufficient queue management for IGMP packets.
- CVE-2026-20280High
A vulnerability in Cisco IOS XR Software was discovered during an internal security review. It relates to improper checking or handling of exceptional conditions, classified as CWE-703.
- CVE-2026-20278High
A vulnerability in Cisco IOS XR Software was discovered during an internal security review. It relates to improper neutralization issues, classified as CWE-707.
- CVE-2026-20277High
A vulnerability in Cisco IOS XR Software was discovered during an internal security review. It relates to protection mechanism failure issues, classified as CWE-693.
- CVE-2026-20276High
A vulnerability in Cisco IOS XR Software was discovered during an internal security review. It relates to insufficient control flow management issues, classified as CWE-691.
- CVE-2026-20275High
A vulnerability in Cisco IOS XR Software was discovered during an internal security review. It relates to incorrect calculation issues, classified as CWE-682.
Original NVD description (English source)
A vulnerability in the management interface access control list (ACL) processing feature in Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass configured ACLs for the SSH, NetConf, and gRPC features. This vulnerability exists because management interface ACLs have not been supported on Cisco IOS XR Software Packet I/O infrastructure platforms for Linux-handled features such as SSH, NetConf, or gRPC. An attacker could exploit this vulnerability by attempting to send traffic to an affected device. A successful exploit could allow the attacker to bypass an ingress ACL that is applied on the management interface of the affected device.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS