A flaw was found in grub2 in versions prior to 2.06. Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
NOTE: The following CVSS v3.0 metrics and score provided are preliminary and subject to review.
|Base Score:||6.7||Base Metrics:||AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H|
|Access Vector:||Local network||Attack Complexity:||Low|
|Privileges Required:||High||User Interaction:||None|
|Integrity Impact:||High||Availability Impact:||High|
|Oracle Linux version 7 (grub2)||ELSA-2021-0699||2021-03-05|
|Oracle Linux version 7 (grub2)||ELSA-2021-9076||2021-03-02|
|Oracle Linux version 8 (grub2)||ELSA-2021-0696||2021-03-05|
|Oracle Linux version 8 (grub2)||ELSA-2021-9077||2021-03-02|
This page is generated automatically and has not been checked for errors or omissions. For clarification or corrections please contact the Oracle Linux ULN team