CVE-2025-20143: Cisco IOS XR Software Secure Boot Bypass Vulnerability

Severity: medium (CVSS 6.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-03-12 · updated 2026-06-17
Weakness: CWE-347

Description

A vulnerability in the boot process of Cisco IOS XR Software could allow an authenticated, local attacker with high privileges to bypass the Secure Boot functionality and load unverified software on an affected device. To exploit this vulnerability, the attacker must have root-system privileges on the affected device. This vulnerability is due to insufficient verification of modules in the software load process. An attacker could exploit this vulnerability by manipulating the loaded binaries to bypass some of the integrity checks that are performed during the booting process. A successful exploit could allow the attacker to control the boot configuration, which could enable them to bypass the requirement to run Cisco-signed images or alter the security properties of the running system. Note: This vulnerability affects Cisco IOS XR Software, not the Secure Boot feature. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

Affected products

Cisco IOS XR Software: before 7.9.1 — fixed in 7.9.1

How to fix

Upgrade to a fixed version: Cisco IOS XR Software 7.9.1. Check the vendor advisory for mitigations.

References

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