CVE-2020-27749
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.
Does this matter?
Lower severity and a low EPSS score (0.57%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 6.7 MEDIUMCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.57% probability · 46th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-121, CWE-787
- Affected
- gnu/grub2 · redhat/enterprise linux · redhat/enterprise linux server aus · redhat/enterprise linux server eus · redhat/enterprise linux server tus · redhat/enterprise linux workstation · fedoraproject/fedora · netapp/ontap select deploy administration utility
- Source
- secalert@redhat.com
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1899966Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/
- https://security.gentoo.org/glsa/202104-05Third Party Advisory
- https://security.netapp.com/advisory/ntap-20220325-0001/Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1899966Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/
- https://security.gentoo.org/glsa/202104-05Third Party Advisory
- https://security.netapp.com/advisory/ntap-20220325-0001/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.