CVE-2025-0677

Grub2: ufs: integer overflow may lead to heap based out-of-bounds write when handling symlinks

Published Feb 19, 2025 CVSS 3.1 · 6.4 Medium EPSS < 1% KEV · Not listed
Description
A flaw was found in grub2. When performing a symlink lookup, the grub's UFS module checks the inode's data size to allocate the internal buffer to read the file content, however, it fails to check if the symlink data size has overflown. When this occurs, grub_malloc() may be called with a smaller value than needed. When further reading the data from the disk into the buffer, the grub_ufs_lookup_symlink() function will write past the end of the allocated size. An attack can leverage this by crafting a malicious filesystem, and as a result, it will corrupt data stored in the heap, allowing for arbitrary code execution used to by-pass secure boot mechanisms.

Remediation

Vendor Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4685-1 grub2 security update
EUVD EUVD EUVD-2025-4654 A flaw was found in grub2. When performing a symlink lookup, the grub's UFS module checks the inode's data size to allocate the internal buffer to read the file content, however, it fails to check if the symlink data size has overflown. When this occurs, grub_malloc() may be called with a smaller value than needed. When further reading the data from the disk into the buffer, the grub_ufs_lookup_symlink() function will write past the end of the allocated size. An attack can leverage this by crafting a malicious filesystem, and as a result, it will corrupt data stored in the heap, allowing for arbitrary code execution used to by-pass secure boot mechanisms.
History
Type Values Removed Values Added
First Time appeared Redhat rhel Els
CPEs cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/a:redhat:enterprise_linux:8
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els
Type Values Removed Values Added
CPEs cpe:/o:redhat:rhivos:1
Vendors & Products Redhat rhivos
Type Values Removed Values Added
First Time appeared Redhat rhivos
CPEs cpe:/o:redhat:rhivos:1
Vendors & Products Redhat rhivos
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:10 cpe:/o:redhat:enterprise_linux:10.0
References
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:10
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:9
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:9::baseos
References
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description No description is available for this CVE. A flaw was found in grub2. When performing a symlink lookup, the grub's UFS module checks the inode's data size to allocate the internal buffer to read the file content, however, it fails to check if the symlink data size has overflown. When this occurs, grub_malloc() may be called with a smaller value than needed. When further reading the data from the disk into the buffer, the grub_ufs_lookup_symlink() function will write past the end of the allocated size. An attack can leverage this by crafting a malicious filesystem, and as a result, it will corrupt data stored in the heap, allowing for arbitrary code execution used to by-pass secure boot mechanisms.
Title grub2: UFS: Integer overflow may lead to heap based out-of-bounds write when handling symlinks Grub2: ufs: integer overflow may lead to heap based out-of-bounds write when handling symlinks
First Time appeared Redhat
Redhat enterprise Linux
Redhat openshift
CPEs cpe:/a:redhat:openshift:4
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
Redhat openshift
References
Type Values Removed Values Added
Description No description is available for this CVE.
Title grub2: UFS: Integer overflow may lead to heap based out-of-bounds write when handling symlinks
Weaknesses CWE-787
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.4, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 5, 2026, 2:46 PM
Reserved
Jan 23, 2025, 4:24 PM
Status
Deferred
Published
Feb 19, 2025, 7:15 PM
Modified
Nov 5, 2026, 3:17 PM
Severity
Moderate
Public date
Feb 18, 2025, 6:00 PM