In the Linux kernel, the following vulnerability has been resolved: efi/capsule-loader: fix incorrect sizeof in phys array reallocation The… (CVE-2026-53047)
In the Linux kernel, the following vulnerability has been resolved: efi/capsule-loader: fix incorrect sizeof in phys array reallocation The krealloc() call for cap_info->phys in __efi_capsule_setup_info() uses sizeof(phys_addr_t *) instead of sizeof(phys_addr_t), which might be causing an undersized allocation. The allocation is also inconsistent with the initial array allocation in efi_capsule_open() that allocates one entry with sizeof(phys_addr_t), and the efi_capsule_write() function that stores phys_addr_t values (not pointers) via page_to_phys(). On 64-bit systems where sizeof(phys_addr_t) == sizeof(phys_addr_t *), this goes unnoticed. On 32-bit systems with PAE where phys_addr_t is 64-bit but pointers are 32-bit, this allocates half the required space, which might lead to a heap buffer overflow when storing physical addresses. This is similar to the bug fixed in commit fccfa646ef36 ("efi/capsule-loader: fix incorrect allocation size") which fixed the same issue at the initial allocation site.
In the Linux kernel, the following vulnerability has been resolved: efi/capsule-loader: fix incorrect sizeof in phys array reallocation The… (CVE-2026-53047)
Description
In the Linux kernel, the following vulnerability has been resolved: efi/capsule-loader: fix incorrect sizeof in phys array reallocation The krealloc() call for cap_info->phys in __efi_capsule_setup_info() uses sizeof(phys_addr_t *) instead of sizeof(phys_addr_t), which might be causing an undersized allocation. The allocation is also inconsistent with the initial array allocation in efi_capsule_open() that allocates one entry with sizeof(phys_addr_t), and the efi_capsule_write() function that stores phys_addr_t values (not pointers) via page_to_phys(). On 64-bit systems where sizeof(phys_addr_t) == sizeof(phys_addr_t *), this goes unnoticed. On 32-bit systems with PAE where phys_addr_t is 64-bit but pointers are 32-bit, this allocates half the required space, which might lead to a heap buffer overflow when storing physical addresses. This is similar to the bug fixed in commit fccfa646ef36 ("efi/capsule-loader: fix incorrect allocation size") which fixed the same issue at the initial allocation site.
CVSS v3.1
Score 5.5medium
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-jp44-vj5f-4fr8
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-53047"]
- Ecosystems
- []
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a5fcf481010f89cc2152d0e
Added to database: 07/21/2026, 19:58:00 UTC
Last updated: 07/31/2026, 19:24:47 UTC
Views: 9
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