CVE-2023-52976 efi: fix potential NULL deref in efi_mem_reserve_persistent

What is CVE-2023-52976?

CVE-2023-52976 is a medium-severity vulnerability in Linux kernel, published on 27 Mar 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

efi: fix potential NULL deref in efi_mem_reserve_persistent

When iterating on a linked list, a result of memremap is dereferenced without checking it for NULL.

This patch adds a check that falls back on allocating a new page in case memremap doesn't succeed.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

[ardb: return -ENOMEM instead of breaking out of the loop]

Weakness: CWE-476

Which versions are affected by CVE-2023-52976?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-52976?

Apply the vendor's patch.

Is CVE-2023-52976 being exploited?

There is no known exploitation of CVE-2023-52976 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-52976, DEBIAN-CVE-2023-52976, GHSA-fx88-897w-ccgj, UBUNTU-CVE-2023-52976.