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NVD / CVE Program· CNA Linux

CVE-2025-39843: mm: slub: avoid wake up kswapd in set_track_prepare

MediumCVSS 5.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • 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: 0.11% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 243b705a90ed8449f561a271cf251fd2e939f3db, 522ffe298627cfe72539d72167c2e20e72b5e856, 850470a8413a8a78e772c4f6bd9fe81ec6bd5b0f.

Low priority for now. Upgrade to Linux Linux 243b705a90ed8449f561a271cf251fd2e939f3db, 522ffe298627cfe72539d72167c2e20e72b5e856, 850470a8413a8a78e772c4f6bd9fe81ec6bd5b0f 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: slub: avoid wake up kswapd in set_track_prepare set_track_prepare() can incur lock recursion. The issue is that it is called from hrtimer_start_range_ns holding the per_cpu(hrtimer_bases)[n].lock, but when enabled CONFIG_DEBUG_OBJECTS_TIMERS, may wake up kswapd in set_track_prepare, and try to hold the per_cpu(hrtimer_bases)[n].lock. Avoid deadlock caused by implicitly waking up kswapd by passing in allocation flags, which do not contain __GFP_KSWAPD_RECLAIM in the debug_objects_fill_pool() case. Inside stack depot they are processed by gfp_nested_mask(). Since ___slab_alloc() has preemption disabled, we mask out __GFP_DIRECT_RECLAIM from the flags there. The oops looks something like: BUG: spinlock recursion on CPU#3, swapper/3/0 lock: 0xffffff8a4bf29c80, .magic: dead4ead, .owner: swapper/3/0, .owner_cpu: 3 Hardware name: Qualcomm Technologies, Inc. Popsicle based on SM8850 (DT) Call trace: spin_bug+0x0 _raw_spin_lock_irqsave+0x80 hrtimer_try_to_cancel+0x94 task_contending+0x10c enqueue_dl_entity+0x2a4 dl_server_start+0x74 enqueue_task_fair+0x568 enqueue_task+0xac do_activate_task+0x14c ttwu_do_activate+0xcc try_to_wake_up+0x6c8 default_wake_function+0x20 autoremove_wake_function+0x1c __wake_up+0xac wakeup_kswapd+0x19c wake_all_kswapds+0x78 __alloc_pages_slowpath+0x1ac __alloc_pages_noprof+0x298 stack_depot_save_flags+0x6b0 stack_depot_save+0x14 set_track_prepare+0x5c ___slab_alloc+0xccc __kmalloc_cache_noprof+0x470 __set_page_owner+0x2bc post_alloc_hook[jt]+0x1b8 prep_new_page+0x28 get_page_from_freelist+0x1edc __alloc_pages_noprof+0x13c alloc_slab_page+0x244 allocate_slab+0x7c ___slab_alloc+0x8e8 kmem_cache_alloc_noprof+0x450 debug_objects_fill_pool+0x22c debug_object_activate+0x40 enqueue_hrtimer[jt]+0xdc hrtimer_start_range_ns+0x5f8 ...

Published
Sep 19, 2025
Updated
Oct 19, 2026
EPSS
0.1% · 1th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

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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
debiandebian linux

Affected versions

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

  • debian debian linux11.0
  • linux linux kernel5.19 and later · before 6.1.151
  • linux linux kernel6.2 and later · before 6.6.105
  • linux linux kernel6.7 and later · before 6.12.46
  • linux linux kernel6.13 and later · before 6.16.6
  • linux linux kernel6.17

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

    • 5.19affected
    • 5cf909c553e9efed573811de4b3f5172898d5515 and later · before 994b03b9605d36d814c611385fbf90ca6db20aa8affected · git
    • 5cf909c553e9efed573811de4b3f5172898d5515 and later · before 522ffe298627cfe72539d72167c2e20e72b5e856affected · git
    • 5cf909c553e9efed573811de4b3f5172898d5515 and later · before 243b705a90ed8449f561a271cf251fd2e939f3dbaffected · git
    • 5cf909c553e9efed573811de4b3f5172898d5515 and later · before eb3240ffd243bfb8b1e9dc568d484ecf9fd660abaffected · git
    • 5cf909c553e9efed573811de4b3f5172898d5515 and later · before 850470a8413a8a78e772c4f6bd9fe81ec6bd5b0faffected · git
    • before 5.19not affected · semver
    • 6.1.151 and later · up to and including 6.1.*not affected · semver
    • 6.6.105 and later · up to and including 6.6.*not affected · semver
    • 6.12.46 and later · up to and including 6.12.*not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:10kernel-abi-stablelistsbefore 6.12.0-124.27.1.el10_16.12.0-124.27.1.el10_1
AlmaLinux:10kernel-docbefore 6.12.0-124.27.1.el10_16.12.0-124.27.1.el10_1
AlmaLinux:9kernelbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64kbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-corebefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debugbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debug-corebefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debug-develbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debug-devel-matchedbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debug-modulesbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-debug-modules-extrabefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-develbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-devel-matchedbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-64k-modules-extrabefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-abi-stablelistsbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-debug-develbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-debug-devel-matchedbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-develbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-devel-matchedbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-docbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-headersbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-zfcpdump-develbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9kernel-zfcpdump-devel-matchedbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7
AlmaLinux:9perfbefore 5.14.0-611.9.1.el9_75.14.0-611.9.1.el9_7

+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-2025-39841Sep 19, 2025 · scsi: lpfc: Fix buffer free/clear order in deferred receive path
    31Monitor
  • ← EarlierCVE-2025-39842Sep 19, 2025 · ocfs2: prevent release journal inode after journal shutdown
    22Monitor
  • Later →CVE-2025-39844Sep 19, 2025 · mm: move page table sync declarations to linux/pgtable.h
    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 Linux243b705a90ed8449f561a271cf251fd2e939f3dbVendor (CNA)
Linux Linux522ffe298627cfe72539d72167c2e20e72b5e856Vendor (CNA)
Linux Linux850470a8413a8a78e772c4f6bd9fe81ec6bd5b0fVendor (CNA)
Linux Linux994b03b9605d36d814c611385fbf90ca6db20aa8Vendor (CNA)
Linux Linuxeb3240ffd243bfb8b1e9dc568d484ecf9fd660abVendor (CNA)
almalinux:kernel5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-core5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-core5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel-matched5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules-extra5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel-matched5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-modules-extra5.14.0-611.9.1.el9_7 · AlmaLinux:9Package registry (OSV)
debian:linux6.1.153-1 · Debian:12Package registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-devel-matched0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debuginfo0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-aarch640:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-ppc64le0:5.14.0-611.9.1.el9_7 · Red Hat:enterprise_linux:9::appstreamPackage 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.
  • No special conditions are required; it is repeatable.

If successful

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

Weakness class (CWE)

CWE-667 · Improper Locking

CVSS vector

CVSS:3.1/AV:L/AC:L/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.

Change log

  1. Fix✗ → ✓

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

References

Show all references (6 more)

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

All records