CVE-2023-4389: Kernel: btrfs: double free in btrfs_get_root_ref()

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-08-16 · updated 2026-06-17
Weakness: CWE-415

Description

A flaw was found in btrfs_get_root_ref in fs/btrfs/disk-io.c in the btrfs filesystem in the Linux Kernel due to a double decrement of the reference count. This issue may allow a local attacker with user privilege to crash the system or may lead to leaked internal kernel information.

Affected products

Linux kernel: from 5.7 before 5.10.112; from 5.11 before 5.15.35; from 5.16 before 5.17.4 — fixed in 5.10.112, 5.15.35, 5.17.4

How to fix

Upgrade to a fixed version: Linux kernel 5.10.112, 5.15.35, 5.17.4. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2023-4389
https://bugzilla.redhat.com/show_bug.cgi?id=2219271
https://patchwork.kernel.org/project/linux-btrfs/patch/20220324134454.15192-1-baijiaju1990@gmail.com/
https://access.redhat.com/security/cve/CVE-2023-4389
https://bugzilla.redhat.com/show_bug.cgi?id=2219271
https://patchwork.kernel.org/project/linux-btrfs/patch/20220324134454.15192-1-baijiaju1990@gmail.com/

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