CVE-2025-0690: Grub2: read: integer overflow may lead to out-of-bounds write

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-02-24 · updated 2026-10-21
Weakness: CWE-787

Description

The read command is used to read the keyboard input from the user, while reads it keeps the input length in a 32-bit integer value which is further used to reallocate the line buffer to accept the next character. During this process, with a line big enough it's possible to make this variable to overflow leading to a out-of-bounds write in the heap based buffer. This flaw may be leveraged to corrupt grub's internal critical data and secure boot bypass is not discarded as consequence.

Affected products

Red Hat OpenShift Container Platform 4.18: all versions
Red Hat Enterprise Linux 9: all versions — fixed in 1:2.06-104.el9_6

How to fix

Upgrade to a fixed version: Red Hat Enterprise Linux 9 1:2.06-104.el9_6. Check the vendor advisory for mitigations.

References

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