Описание
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.
Отчет
Red Hat Product Security has rated this vulnerability with Moderate severity, as it requires high privileges to exploit. Within regulated environments, a combination of the following controls acts as a significant barrier to successfully exploiting a CWE-787: Out-of-bounds Write vulnerability and therefore downgrades the severity of this particular CVE from Moderate to Low. The platform enforces hardening guidelines to apply the most restrictive settings necessary for operational requirements. Baseline configurations and system controls ensure secure software settings, while least functionality reduces the attack surface by disabling unauthorized services and ports. The environment employs IPS/IDS and antimalware solutions to detect and prevent malicious code exploiting out-of-bounds write vulnerabilities, using mechanisms such as file integrity monitoring and patch management. Robust input validation and error handling ensure all user inputs are thoroughly validated, preventing instability, data exposure, or privilege escalation. Finally, the platform uses memory protection mechanisms such as Data Execution Prevention (DEP) and Address Space Layout Randomization (ASLR) to strengthen resilience against out-of-bounds write exploits.
Меры по смягчению последствий
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.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 10 | grub2 | Affected | ||
| Red Hat Enterprise Linux 7 | grub2 | Out of support scope | ||
| Red Hat Enterprise Linux 8 | grub2 | Out of support scope | ||
| Red Hat OpenShift Container Platform 4 | rhcos | Fix deferred | ||
| Red Hat Enterprise Linux 9 | grub2 | Fixed | RHSA-2025:6990 | 13.05.2025 |
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Дополнительная информация
Статус:
EPSS
6.4 Medium
CVSS3
Связанные уязвимости
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.
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.
A flaw was found in grub2. When performing a symlink lookup, the grub' ...
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.
Уязвимость компонента UFS загрузчика операционных систем Grub2, позволяющая нарушителю вызвать отказ в обслуживании
EPSS
6.4 Medium
CVSS3