Grub2
CVE-2020-15707
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V15 - Secure Coding and Architecture Concurrency control, locking
MITRE ATT&CK
1 technique across 1 tactic: Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.4 (MEDIUM). Attack characteristics: local attack vector, high complexity, high privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not. Rated medium severity (CVSS 6.4). Public exploit code available.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified under CWE-362. Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions.04 and prior versions. Affected products include: Gnu Grub2, Redhat Enterprise Linux Atomic Host, Redhat Openshift Container Platform, Redhat Enterprise Linux, Microsoft Windows 10. Version information: version 2.04.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. This issue affects GRUB2 version 2.04 and prior versions.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
Race conditions occur when multiple concurrent requests exploit the brief time gap between checking a condition and acting upon it (TOCTOU - Time of Check, Time of Use).
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)NVD
Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate attackers to bypass authentication, ob
An out-of-bounds write flaw was found in grub2's NTFS filesystem driver. Rated high severity (CVSS 7.8), this vulnerabil
GRUB2 does not call the module fini functions on exit, leading to Debian/Ubuntu's peimage GRUB2 module leaving UEFI syst
GNU GRUB (aka GRUB2) through 2.12 has a heap-based buffer overflow in fs/hfs.c via crafted sblock data in an HFS filesys
An out-of-bounds read flaw was found on grub2's NTFS filesystem driver. Rated medium severity (CVSS 4.6), this vulnerabi
A buffer overflow was found in grub_font_construct_glyph(). Rated high severity (CVSS 8.6), this vulnerability is no aut
A flaw was found in grub2 in versions prior to 2.06. Rated high severity (CVSS 8.2), this vulnerability is low attack co
A flaw was found in grub2, prior to version 2.06. Rated high severity (CVSS 8.2), this vulnerability is low attack compl
A flaw was found in grub2. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch
A flaw was found in the HFS filesystem. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No
When reading data from a hfs filesystem, grub's hfs filesystem module uses user-controlled parameters from the filesyste
When reading data from disk, the grub's UDF filesystem module utilizes the user controlled data length metadata to alloc
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB