CVE-2021-47342

Updated: 2026-02-27 01:41:27.077962

Description:

In the Linux kernel, the following vulnerability has been resolved: ext4: fix possible UAF when remounting r/o a mmp-protected file system After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over. Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd(). Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>


Links NIST CIRCL RHEL Ubuntu

Severity

Severity Score
CVSS Version 2.x 0.0
CVSS Version 3.x HIGH 7.8

Status

OS name Project name Version Score Severity Status Errata Last updated

Statement

CentOS 6 ELS kernel 2.6.32 7.8 HIGH Not Vulnerable 2025-02-24 06:42:13 Not affected: this UAF only exists in ext4’s MMP stop path introduced after commit 618f003199c6, w...
CentOS 7 ELS kernel 3.10.0 7.8 HIGH Released CLSA-2025:1762332910 2025-11-21 21:24:20
CloudLinux 6 ELS kernel 2.6.32 7.8 HIGH Not Vulnerable 2025-02-24 06:42:13
Oracle Linux 6 ELS kernel 2.6.32 7.8 HIGH Not Vulnerable 2025-02-24 06:42:13 Not affected: this UAF only exists in ext4’s MMP stop path introduced after commit 618f003199c6, w...
Oracle Linux 7 ELS kernel 3.10.0 7.8 HIGH Released CLSA-2025:1762244592 2025-11-05 04:52:03
RHEL 7 ELS kernel 3.10.0 7.8 HIGH Released CLSA-2025:1762244848 2025-11-05 15:42:52
Ubuntu 16.04 ELS linux-hwe 4.15.0 7.8 HIGH Released CLSA-2025:1742321198 2025-03-18 23:45:02
Ubuntu 16.04 ELS linux 4.4.0 7.8 HIGH Released CLSA-2025:1747430034 2025-05-18 05:12:13
Ubuntu 18.04 ELS linux 4.15.0 7.8 HIGH Released CLSA-2025:1742319747 2025-03-20 05:17:09