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NVD / CVE Program· CNA Linux

CVE-2023-53401: mm: kmem: fix a NULL pointer dereference in obj_stock_flush_required()

Noroxi assessment

Priority: Monitor (action score 18/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.13% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: Linux Linux 33391c7e1a2ad612bf3922cc168cb09a46bbe236, 33d9490b27e5d8da4444aefd714a4f50189db978, 3b8abb3239530c423c0b97e42af7f7e856e1ee96; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes.

Low priority for now. Upgrade to Linux Linux 33391c7e1a2ad612bf3922cc168cb09a46bbe236, 33d9490b27e5d8da4444aefd714a4f50189db978, 3b8abb3239530c423c0b97e42af7f7e856e1ee96; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: mm: kmem: fix a NULL pointer dereference in obj_stock_flush_required() KCSAN found an issue in obj_stock_flush_required(): stock->cached_objcg can be reset between the check and dereference: ================================================================== BUG: KCSAN: data-race in drain_all_stock / drain_obj_stock write to 0xffff888237c2a2f8 of 8 bytes by task 19625 on cpu 0: drain_obj_stock+0x408/0x4e0 mm/memcontrol.c:3306 refill_obj_stock+0x9c/0x1e0 mm/memcontrol.c:3340 obj_cgroup_uncharge+0xe/0x10 mm/memcontrol.c:3408 memcg_slab_free_hook mm/slab.h:587 [inline] __cache_free mm/slab.c:3373 [inline] __do_kmem_cache_free mm/slab.c:3577 [inline] kmem_cache_free+0x105/0x280 mm/slab.c:3602 __d_free fs/dcache.c:298 [inline] dentry_free fs/dcache.c:375 [inline] __dentry_kill+0x422/0x4a0 fs/dcache.c:621 dentry_kill+0x8d/0x1e0 dput+0x118/0x1f0 fs/dcache.c:913 __fput+0x3bf/0x570 fs/file_table.c:329 ____fput+0x15/0x20 fs/file_table.c:349 task_work_run+0x123/0x160 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xcf/0xe0 kernel/entry/common.c:171 exit_to_user_mode_prepare+0x6a/0xa0 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff888237c2a2f8 of 8 bytes by task 19632 on cpu 1: obj_stock_flush_required mm/memcontrol.c:3319 [inline] drain_all_stock+0x174/0x2a0 mm/memcontrol.c:2361 try_charge_memcg+0x6d0/0xd10 mm/memcontrol.c:2703 try_charge mm/memcontrol.c:2837 [inline] mem_cgroup_charge_skmem+0x51/0x140 mm/memcontrol.c:7290 sock_reserve_memory+0xb1/0x390 net/core/sock.c:1025 sk_setsockopt+0x800/0x1e70 net/core/sock.c:1525 udp_lib_setsockopt+0x99/0x6c0 net/ipv4/udp.c:2692 udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2817 sock_common_setsockopt+0x61/0x70 net/core/sock.c:3668 __sys_setsockopt+0x1c3/0x230 net/socket.c:2271 __do_sys_setsockopt net/socket.c:2282 [inline] __se_sys_setsockopt net/socket.c:2279 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2279 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffff8881382d52c0 -> 0xffff888138893740 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 19632 Comm: syz-executor.0 Not tainted 6.3.0-rc2-syzkaller-00387-g534293368afa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Fix it by using READ_ONCE()/WRITE_ONCE() for all accesses to stock->cached_objcg.

MediumCVSS 4.7 · v3.1—No exploit Fix available
Published
Sep 18, 2025
Updated
Jun 17, 2026
EPSS
0.1% · 3th percentile

Report tools

JSON

Action score

18

Monitor

Low priority for now.

CVSS
18 / 40 · 4.7 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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  • when exploit code appears or is weaponized
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  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel5.9 and later · before 6.1.45
  • linux linux kernel6.2 and later · before 6.4.10

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 5.9affected
    • bf4f059954dcb221384b2f784677e19a13cd4bdb and later · before 33d9490b27e5d8da4444aefd714a4f50189db978affected · git
    • bf4f059954dcb221384b2f784677e19a13cd4bdb and later · before 33391c7e1a2ad612bf3922cc168cb09a46bbe236affected · git
    • bf4f059954dcb221384b2f784677e19a13cd4bdb and later · before 3b8abb3239530c423c0b97e42af7f7e856e1ee96affected · git
    • before 5.9not affected · semver
    • 6.1.45 and later · up to and including 6.1.*not affected · semver
    • 6.4.10 and later · up to and including 6.4.*not affected · semver
    • 6.5 and laternot affected · original_commit_for_fix

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8bpftoolbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernelbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-corebefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-cross-headersbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-debugbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-debug-corebefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-debug-develbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-develbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-docbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-headersbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-modulesbefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-modules-extrabefore 4.18.0-553.89.1.el8_104.18.0-553.89.1.el8_10
AlmaLinux:8kernel-rtbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-corebefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-debugbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-debug-corebefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-debug-develbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-debug-modulesbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-debug-modules-extrabefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-develbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10
AlmaLinux:8kernel-rt-modulesbefore 4.18.0-553.89.1.rt7.430.el8_104.18.0-553.89.1.rt7.430.el8_10

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2023-53399Sep 18, 2025 · ksmbd: fix NULL pointer dereference in smb2_get_info_filesystem()
    22Monitor
  • ← EarlierCVE-2023-53400Sep 18, 2025 · ALSA: hda: Fix Oops by 9.1 surround channel names
    22Monitor
  • Later →CVE-2023-53402Sep 18, 2025 · kernel/printk/index.c: fix memory leak with using debugfs_lookup()
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux33391c7e1a2ad612bf3922cc168cb09a46bbe236Vendor (CNA)
Linux Linux33d9490b27e5d8da4444aefd714a4f50189db978Vendor (CNA)
Linux Linux3b8abb3239530c423c0b97e42af7f7e856e1ee96Vendor (CNA)
cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0Release NotesMicrosoft (MSRC)
almalinux:bpftool4.18.0-553.89.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.89.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules-extra4.18.0-553.89.1.rt7.430.el8_10 · AlmaLinux:8Package registry (OSV)
debian:linux6.1.52-1 · Debian:12Package registry (OSV)
red hat:bpftool-debuginfo0:7.3.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debug-devel-matched0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debuginfo0:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-aarch640:5.14.0-427.97.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
rocky linux:kernel0:4.18.0-553.89.1.el8_10 · Rocky Linux:8Package registry (OSV)

+1

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-476 · NULL Pointer Dereference

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records