Privilege escalation in Insyde H2O UEFI

1) Exposed dangerous method or function

EUVDB-ID: #VU110699

Risk: Low

CVSSv4.0: 4 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-4275

CWE-ID: CWE-749 - Exposed Dangerous Method or Function

Exploit availability: No

Description

The vulnerability allows an attacker to escalate privileges on the system.

The vulnerability exists due to usage of an unprotected NVRAM variable. An attacker with physical access to the system can inject their own certificate in this variable and subsequently run arbitrary firmware (signed by the injected certificate) during the early boot process within the UEFI environment.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

InsydeH2O Kernel: All versions

CPE2.3

• cpe:2.3:h:insyde_software:insyde_kernel:*:*:*:*:*:*:*:*

External links

https://www.kb.cert.org/vuls/id/211341

Q & A

Can this vulnerability be exploited remotely?

No. The attacker should have physical access to the system in order to successfully exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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