#VU118663 Out-of-bounds write in grub - CVE-2025-61661
Published: November 21, 2025
Vulnerability identifier: #VU118663
Vulnerability risk: Low
CVSSv4.0: CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2025-61661
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
grub
grub
Software vendor:
GNU
GNU
Description
The vulnerability allows an attacker to perform a denial of service attack.
The vulnerability exists due to a boundary error within the grub_usb_get_string() function in grub-core/commands/usbtest.c. An attacker with physical access to the system can connect a specially crafted USB device during the boot sequence, trigger an out-of-bounds write and perform a denial of service (DoS) attack.
Remediation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.