CVE-2020-15706

Name: CVE-2020-15706
Creator: NVD / NIST
Published: 2020-07-29T18:15:14.42+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.4/10EPSS 0.98%

Last modified Jun 17, 2026

CVE-2020-15706 is a medium-severity vulnerability rated 6.4/10 on the CVSS scale. 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.. EPSS estimates a 0.98% chance of exploitation in the next 30 days.

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:H

EPSS Probability

0.98%

57.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Gnu	Grub2	<= 2.04
Redhat	Enterprise Linux Atomic Host	All versions
Redhat	Openshift Container Platform	4.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	20.04
Debian	Debian Linux	10.0
Redhat	Enterprise Linux	7.0
Redhat	Enterprise Linux	8.0
Suse	Suse Linux Enterprise Server	11
Suse	Suse Linux Enterprise Server	12
Suse	Suse Linux Enterprise Server	15
Microsoft	Windows 10	All versions
Microsoft	Windows 10	1607
Microsoft	Windows 10	1709
Microsoft	Windows 10	1803
Microsoft	Windows 10	1809
Microsoft	Windows 10	1903
Microsoft	Windows 10	1909
Microsoft	Windows 10	2004
Microsoft	Windows 8.1	All versions
Microsoft	Windows Rt 8.1	All versions
Microsoft	Windows Server 2012	All versions
Microsoft	Windows Server 2012	r2
Microsoft	Windows Server 2016	All versions
Microsoft	Windows Server 2016	1903
Microsoft	Windows Server 2016	1909
Microsoft	Windows Server 2016	2004
Microsoft	Windows Server 2019	All versions
Opensuse	Leap	15.1
Opensuse	Leap	15.2

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
Status: Modified

Frequently Asked Questions

What is CVE-2020-15706?

How severe is CVE-2020-15706?

CVE-2020-15706 has a CVSS score of 6.4/10 (MEDIUM severity). The EPSS model estimates a 0.98% probability of exploitation in the next 30 days.

How do I fix CVE-2020-15706?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-15706?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST