CVE-2026-53047: Linux kernel · efi/capsule-loader: fix incorrect sizeof in phys array reallocation
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in e0e6b14995fd6fa2c0df8c712d76ab32f0694c31 : update Linux kernel when convenient.
Data as of 6 Nov 2026, 16:34 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in e0e6b14995fd6fa2c0df8c712d76ab32f0694c31, ab3f7098a3a27175b91cfc947950f5c26855801b, 22022cd8851703a58f67615a17bc7e9e8682785b +6
Exploitation evidence
Disclosed: evidence found.
CVE published 24 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
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
- git.kernel.org/stable/c/22022cd8851703a58f67615a17bc7e9e8682785b (opens in a new tab)
- git.kernel.org/stable/c/67adde6bfdfd563a54b045d59aeb9a2d90c80697 (opens in a new tab)
- git.kernel.org/stable/c/608e1f7bc9d171ab26c1fba288c97fc76363c27d (opens in a new tab)
- git.kernel.org/stable/c/8be69e9245f805566bac68ffc8574b64735fd996 (opens in a new tab)
- git.kernel.org/stable/c/5e185330d902b12fe8e6eb4b8514b5d736d8d66d (opens in a new tab)
- git.kernel.org/stable/c/e0e6b14995fd6fa2c0df8c712d76ab32f0694c31 (opens in a new tab)
- git.kernel.org/stable/c/ab3f7098a3a27175b91cfc947950f5c26855801b (opens in a new tab)
- git.kernel.org/stable/c/48a428215782321b56956974f23593e40ce84b7a (opens in a new tab)