CVE-2020-15705
CVE-2020-15705 is a medium-severity vulnerability in Gnu Grub2 with a CVSS 3.x base score of 6.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.
Key facts
- Severity: Medium (CVSS 3.x base score 6.4)
- CVSS v2: 4.4
- EPSS exploit prediction: 1% (70th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-347
- Affected product: Gnu Grub2
- Published:
- Last modified:
Description
GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions.
Frequently asked questions
- What is CVE-2020-15705?
- GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions.
- How severe is CVE-2020-15705?
- CVE-2020-15705 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-15705 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-15705?
- CVE-2020-15705 primarily affects Gnu Grub2. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-15705?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-15705 published?
- CVE-2020-15705 was published on 2020-07-29 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00067.html
- http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00069.html
- http://ubuntu.com/security/notices/USN-4432-1
- http://www.openwall.com/lists/oss-security/2020/07/29/3
- http://www.openwall.com/lists/oss-security/2021/03/02/3
- http://www.openwall.com/lists/oss-security/2021/09/17/2
- http://www.openwall.com/lists/oss-security/2021/09/17/4
- http://www.openwall.com/lists/oss-security/2021/09/21/1
- https://access.redhat.com/security/vulnerabilities/grub2bootloader
- https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011
- https://security.gentoo.org/glsa/202104-05
- https://security.netapp.com/advisory/ntap-20200731-0008/
- https://usn.ubuntu.com/4432-1/
- https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass
- https://www.debian.org/security/2020-GRUB-UEFI-SecureBoot
- https://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/
- https://www.openwall.com/lists/oss-security/2020/07/29/3
- https://www.suse.com/c/suse-addresses-grub2-secure-boot-issue/
- https://www.suse.com/support/kb/doc/?id=000019673
Affected products (32)
- cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:enterprise_linux_atomic_host:-:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:suse:suse_linux_enterprise_server:11:*:*:*:*:*:*:*
- cpe:2.3:o:suse:suse_linux_enterprise_server:12:*:*:*:*:*:*:*
- cpe:2.3:o:suse:suse_linux_enterprise_server:15:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1607:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1709:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1803:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1809:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1903:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:1903:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:1909:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*
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