CVE-2025-20143
Cisco IOS XR Software Secure Boot Bypass Vulnerability
Public exploit available. Not confirmed exploited in the wild yet. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
0 sources with a proof of concept or module.
Exploit links, PoCs and Metasploit modules after sign-in- EPSS
0.1% chance of exploitation activity in the next 30 days, which ranks it in the 1st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 470 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Scored 6.7 by NVD.
How it is reached
- Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required HighRequires admin or elevated privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-lkm-zNErZjbZ
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-lkm-zNErZjbZ&
And 2 more references. See all after sign-in
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