CVE-2020-15706

GRUB2 contains a race condition leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing.

Description

GRUB2 contains a race condition in grub_script_function_create() leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing, leading to arbitrary code execution and secure boot restriction bypass. This issue affects GRUB2 version 2.04 and prior versions.

Category

6.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.06%
Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory redhat.com Vendor Advisory suse.com Vendor Advisory suse.com Vendor Advisory debian.org Vendor Advisory ubuntu.com Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory gentoo.org Vendor Advisory gnu.org Vendor Advisory microsoft.com
Affected: Ubuntu grub2 in Ubuntu
Published at:
Updated at:

References

Link Tags
https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/ third party advisory
https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass third party advisory vendor advisory
http://ubuntu.com/security/notices/USN-4432-1 third party advisory vendor advisory
https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot third party advisory vendor advisory
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011 third party advisory patch vendor advisory
https://access.redhat.com/security/vulnerabilities/grub2bootloader third party advisory vendor advisory
https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/ third party advisory vendor advisory
https://www.suse.com/support/kb/doc/?id=000019673 third party advisory vendor advisory
https://www.openwall.com/lists/oss-security/2020/07/29/3 third party advisory mailing list
https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html issue tracking vendor advisory
https://www.debian.org/security/2020/dsa-4735 third party advisory vendor advisory
http://www.openwall.com/lists/oss-security/2020/07/29/3 third party advisory mailing list
https://security.netapp.com/advisory/ntap-20200731-0008/ third party advisory
https://usn.ubuntu.com/4432-1/ third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html mailing list broken link third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html mailing list broken link third party advisory vendor advisory
https://security.gentoo.org/glsa/202104-05 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-15706?
CVE-2020-15706 has been scored as a medium severity vulnerability.
How to fix CVE-2020-15706?
To fix CVE-2020-15706, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-15706 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-15706 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-15706?
CVE-2020-15706 affects Ubuntu grub2 in Ubuntu.
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