CVE-2023-52596: sysctl: Fix out of bounds access for empty sysctl registers

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-03-06 · updated 2026-06-17
Weakness: CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: sysctl: Fix out of bounds access for empty sysctl registers When registering tables to the sysctl subsystem there is a check to see if header is a permanently empty directory (used for mounts). This check evaluates the first element of the ctl_table. This results in an out of bounds evaluation when registering empty directories. The function register_sysctl_mount_point now passes a ctl_table of size 1 instead of size 0. It now relies solely on the type to identify a permanently empty register. Make sure that the ctl_table has at least one element before testing for permanent emptiness.

Affected products

Linux kernel: before 6.6.16; from 6.7 before 6.7.4 — fixed in 6.6.16, 6.7.4

How to fix

Upgrade to a fixed version: Linux kernel 6.6.16, 6.7.4. Check the vendor advisory for mitigations.

References

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