CVE-2023-52976: linux kernel Null Dereference — Fix

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]

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.1.16 — 5.4.232
linux	linux_kernel	5.5 — 5.10.168
linux	linux_kernel	5.11 — 5.15.93
linux	linux_kernel	5.16 — 6.1.11
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/87d4ff18738fd71e7e3c10827c80257da6283697 https://git.kernel.org/stable/c/966d47e1f27c45507c5df82b2a2157e5a4fd3909 https://git.kernel.org/stable/c/a2e6a9ff89f13666a1c3ff7195612ab949ea9afc https://git.kernel.org/stable/c/d8fc0b5fb3e816a4a8684bcd3ed02cbef0fce23c https://git.kernel.org/stable/c/d92a25627bcdf264183670da73c9a60c0bac327e

Frequently Asked Questions

What is CVE-2023-52976? +

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] It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2023-52976? +

CVE-2023-52976 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-52976? +

CVE-2023-52976 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-52976? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-52976