TI-2022-25827 Aliases CVE-2022-50344 GHSA-9f9g-3975-x384

ext4: fix null-ptr-deref in ext4_write_info

LOW 24CWE-476Published 2025-09-16 · Updated 2026-05-11

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Partial Red Hat: 5 fixed, 4 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: ext4: fix null-ptr-deref in ext4_write_info I caught a null-ptr-deref bug as follows: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] CPU: 1 PID: 1589 Comm: umount Not tainted 5.10.0-02219-dirty #339 RIP: 0010:ext4_write_info+0x53/0x1b0 [...] Call Trace: dquot_writeback_dquots+0x341/0x9a0 ext4_sync_fs+0x19e/0x800 __sync_filesystem+0x83/0x100 sync_filesystem+0x89/0xf0 generic_shutdown_super+0x79/0x3e0 kill_block_super+0xa1/0x110 deactivate_locked_super+0xac/0x130 deactivate_super+0xb6/0xd0 cleanup_mnt+0x289/0x400 __cleanup_mnt+0x16/0x20 task_work_run+0x11c/0x1c0 exit_to_user_mode_prepare+0x203/0x210 syscall_exit_to_user_mode+0x5b/0x3a0 do_syscall_64+0x59/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ================================================================== Above issue may happen as follows: ------------------------------------- exit_to_user_mode_prepare task_work_run __cleanup_mnt cleanup_mnt deactivate_super deactivate_locked_super kill_block_super generic_shutdown_super shrink_dcache_for_umount dentry = sb->s_root sb->s_root = NULL <--- Here set NULL sync_filesystem __sync_filesystem sb->s_op->sync_fs > ext4_sync_fs dquot_writeback_dquots sb->dq_op->write_info > ext4_write_info ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2) d_inode(sb->s_root) s_root->d_inode <--- Null pointer dereference To solve this problem, we use ext4_journal_start_sb directly to avoid s_root being used.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00163 5th percentileScored 2026-11-07

Fix Partial Linux (Linux): 4.9.331, 4.14.296, 4.19.262 +6Red Hat: 2 advisoriesRed Hat: 5 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Linux	Linux	3.6 and later	4.9.331, 4.14.296, 4.19.262, 5.4.220, 5.10.150, 5.15.75, 5.19.17, 6.0.3, 6.1	Patch available	CNA

Linux VendorLinux Affected 3.6 and later Fixed in 4.9.331, 4.14.296, 4.19.262, 5.4.220, 5.10.150, 5.15.75, 5.19.17, 6.0.3, 6.1 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	before 4.9.331; 4.10 to before 4.14.296; 4.15 to before 4.19.262; 4.20 to before 5.4.220; 5.5 to before 5.10.150; 5.11 to before 5.15.75; 5.16 to before 5.19.17; 6.0 to before 6.0.3	Vulnerable	Linux

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 4.9.331; 4.10 to before 4.14.296; 4.15 to before 4.19.262; 4.20 to before 5.4.220; 5.5 to before 5.10.150; 5.11 to before 5.15.75; 5.16 to before 5.19.17; 6.0 to before 6.0.3 Vulnerable ·Linux

Remediation

Fix · CNA Linux (Linux) Fixed in 4.9.331, 4.14.296, 4.19.262, 5.4.220, 5.10.150, 5.15.75, 5.19.17, 6.0.3, 6.1

Red Hat 2 advisories

RHSA-2024:3138 Released 2024-05-22 · Red Hat rating Moderate
kernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.el8_10, kernel-4.18.0-553.el8_10, kernel-abi-stablelists-4.18.0-553.el8_10 +19
- Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.el8_10
RHSA-2023:2458 Released 2023-05-09 · Red Hat rating Important
kernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-284.11.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.11.1.el9_2, kernel-64k-devel-5.14.0-284.11.1.el9_2 +10
- Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.0.0-284.11.1.el9_2, kernel-5.14.0-284.11.1.el9_2, kernel-64k-5.14.0-284.11.1.el9_2 +29
- Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-284.11.1.el9_2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 6	Affected	No fix planned: Out of support scope
Red Hat Enterprise Linux 7	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 8	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 9	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 9)	Fixed	RHSA-2023:2458
Red Hat Enterprise Linux BaseOS (v. 8)	Fixed	RHSA-2024:3138
Red Hat Enterprise Linux BaseOS (v. 9)	Fixed	RHSA-2023:2458
Red Hat Enterprise Linux CRB (v. 8)	Fixed	RHSA-2024:3138
Red Hat Enterprise Linux CRB (v. 9)	Fixed	RHSA-2023:2458

Not affected: 1 product

Red Hat Enterprise Linux 10

Timeline

2026-10-02 Threatist record created from CVE-2022-50344
2026-10-03 Alias added: GHSA-9f9g-3975-x384

References

Patch 9

TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3

See all 15278 →

Sources

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