CVE-2026-53047

critical

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.

References

https://git.kernel.org/stable/c/e0e6b14995fd6fa2c0df8c712d76ab32f0694c31

https://git.kernel.org/stable/c/ab3f7098a3a27175b91cfc947950f5c26855801b

https://git.kernel.org/stable/c/8be69e9245f805566bac68ffc8574b64735fd996

https://git.kernel.org/stable/c/67adde6bfdfd563a54b045d59aeb9a2d90c80697

https://git.kernel.org/stable/c/608e1f7bc9d171ab26c1fba288c97fc76363c27d

https://git.kernel.org/stable/c/5e185330d902b12fe8e6eb4b8514b5d736d8d66d

https://git.kernel.org/stable/c/48a428215782321b56956974f23593e40ce84b7a

https://git.kernel.org/stable/c/22022cd8851703a58f67615a17bc7e9e8682785b

Details

Source: Mitre, NVD

Published: 2026-06-24

Updated: 2026-06-24

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.00195