Grub2
CVE-2021-20225
MEDIUM
Severity by source
AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
A flaw was found in grub2 in versions prior to 2.06. The option parser allows an attacker to write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
AnalysisAI
A flaw was found in grub2 in versions prior to 2.06. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Out-of-bounds Write (CWE-787), which allows attackers to write data beyond allocated buffer boundaries leading to code execution or crashes. A flaw was found in grub2 in versions prior to 2.06. The option parser allows an attacker to write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Affected products include: Gnu Grub2, Redhat Enterprise Linux, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Server Tus. Version information: prior to 2.06..
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate write boundaries, use memory-safe languages, enable compiler protections (ASLR, stack canaries).
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
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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
A buffer overflow was found in grub_font_construct_glyph(). Rated high severity (CVSS 8.6), this vulnerability is no aut
An out-of-bounds read flaw was found on grub2's NTFS filesystem driver. Rated medium severity (CVSS 4.6), this vulnerabi
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
Same weakness CWE-787 – Out-of-bounds Write
View allSame technique Buffer Overflow
View allShare
External POC / Exploit Code
Leaving vuln.today