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.
Metrics
CVSS 3.1 6.4/10
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Ubuntu | grub2 in Ubuntu | >= 20.04 LTS, < 2.04-1ubuntu26.1; >= 18.04 LTS, < 2.02-2ubuntu8.16; >= 16.04 LTS, < 2.02~beta2-36ubuntu3.26; >= 14.04 ESM, < 2.02~beta2-9ubuntu1.20 |
References
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.htmlBroken Link, Mailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.htmlBroken Link, Mailing List, Third Party Advisory
- http://ubuntu.com/security/notices/USN-4432-1Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
- https://access.redhat.com/security/vulnerabilities/grub2bootloaderThird Party Advisory
- https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.htmlIssue Tracking, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011Patch, Third Party Advisory, Vendor Advisory
- https://security.gentoo.org/glsa/202104-05Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200731-0008/Third Party Advisory
- https://usn.ubuntu.com/4432-1/Third Party Advisory
- https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypassThird Party Advisory
- https://www.debian.org/security/2020-GRUB-UEFI-SecureBootThird Party Advisory
- https://www.debian.org/security/2020/dsa-4735Third Party Advisory
- https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/Third Party Advisory
- https://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
- https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/Third Party Advisory
- https://www.suse.com/support/kb/doc/?id=000019673Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.htmlBroken Link, Mailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.htmlBroken Link, Mailing List, Third Party Advisory
- http://ubuntu.com/security/notices/USN-4432-1Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
- https://access.redhat.com/security/vulnerabilities/grub2bootloaderThird Party Advisory
- https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.htmlIssue Tracking, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011Patch, Third Party Advisory, Vendor Advisory
- https://security.gentoo.org/glsa/202104-05Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200731-0008/Third Party Advisory
- https://usn.ubuntu.com/4432-1/Third Party Advisory
- https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypassThird Party Advisory
- https://www.debian.org/security/2020-GRUB-UEFI-SecureBootThird Party Advisory
- https://www.debian.org/security/2020/dsa-4735Third Party Advisory
- https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/Third Party Advisory
- https://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
- https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/Third Party Advisory
- https://www.suse.com/support/kb/doc/?id=000019673Third Party Advisory
Timeline
- Published
- Jul 29, 2020
- Last modified
- Jun 17, 2026
- NVD status
- Modified