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NVD / CVE Program· CNA Linux

CVE-2026-64368: mm/slab: do not limit zeroing to orig_size when only red zoning is enabled

Noroxi assessment

Priority: Monitor (action score 32/100)

  • 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: 0.41% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: Linux Linux 0d18ccef142f04433dfb2a0c120cf223d2b8a42c, 2382971aaaef5bf85a651234c64906f59580b8be, 6256899c3a34674bba6076884aedbba49fc695e4; azl3 kernel 6.6.144.1-1 on Azure Linux 3.0 6.6.145.2-1.

Low priority for now. Upgrade to Linux Linux 0d18ccef142f04433dfb2a0c120cf223d2b8a42c, 2382971aaaef5bf85a651234c64906f59580b8be, 6256899c3a34674bba6076884aedbba49fc695e4; azl3 kernel 6.6.144.1-1 on Azure Linux 3.0 6.6.145.2-1 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/slab: do not limit zeroing to orig_size when only red zoning is enabled When init (zeroing) on allocation is requested, for kmalloc() we generally have to zero the full object size even if a smaller size is requested, in order to provide krealloc()'s __GFP_ZERO guarantees. But if we track the requested size, krealloc() uses that information to do the right thing, so we can zero only the requested size. With red zoning also enabled, any extra size became part of the red zone, so it must not be zeroed and thus we must zero only the requested size. However the current check is imprecise, and will trigger also when only SLAB_RED_ZONE is enabled without SLAB_STORE_USER (which enables tracking the requested size). This means enabling red zoning alone can compromise krealloc()'s __GFP_ZERO contract. Fix this by using slub_debug_orig_size() instead, which is the exact check for whether the requested size is tracked. We don't need to care if red zoning is also enabled or not. Also update and expand the comment accordingly.

HighCVSS 8.1 · v3.1—No exploit Fix available
Published
Jul 25, 2026
Updated
Oct 19, 2026
EPSS
0.4% · 35th percentile

Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
32 / 40 · 8.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
8.1
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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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 kernel6.2 and later · before 6.6.145
  • linux linux kernel6.7 and later · before 6.12.96
  • linux linux kernel6.13 and later · before 6.18.39
  • linux linux kernel6.19 and later · before 7.1.4

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

    • 6.2affected
    • 9ce67395f5a0cdec6ce152d26bfda13b98b25c01 and later · before 6256899c3a34674bba6076884aedbba49fc695e4affected · git
    • 9ce67395f5a0cdec6ce152d26bfda13b98b25c01 and later · before 7e706d50fa119eead6376bf0ef973e8d73a96030affected · git
    • 9ce67395f5a0cdec6ce152d26bfda13b98b25c01 and later · before 2382971aaaef5bf85a651234c64906f59580b8beaffected · git
    • 9ce67395f5a0cdec6ce152d26bfda13b98b25c01 and later · before 0d18ccef142f04433dfb2a0c120cf223d2b8a42caffected · git
    • 9ce67395f5a0cdec6ce152d26bfda13b98b25c01 and later · before 648927ceb84021a25a0fbd5673740956f318d534affected · git
    • before 6.2not affected · semver
    • 6.6.145 and later · up to and including 6.6.*not affected · semver
    • 6.12.96 and later · up to and including 6.12.*not affected · semver
    • 6.18.39 and later · up to and including 6.18.*not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:10kernelbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64kbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debugbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-develbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-devel-matchedbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-modulesbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-extrabefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-develbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-devel-matchedbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-modulesbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-modules-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-64k-modules-extrabefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-abi-stablelistsbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-cross-headersbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debugbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debug-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debug-develbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debug-devel-matchedbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debug-modulesbefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2
AlmaLinux:10kernel-debug-modules-corebefore 6.12.0-211.46.1.el10_26.12.0-211.46.1.el10_2

+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-2026-64364Jul 25, 2026 · HID: multitouch: fix out-of-bounds bit access on mt_io_flags
    35Monitor
  • ← EarlierCVE-2026-64366Jul 25, 2026 · HID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert
    35Monitor
  • Later →CVE-2026-64370Jul 25, 2026 · posix-cpu-timers: Fix pid refcount leak in do_cpu_nanosleep() error path
    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 Linux0d18ccef142f04433dfb2a0c120cf223d2b8a42cVendor (CNA)
Linux Linux2382971aaaef5bf85a651234c64906f59580b8beVendor (CNA)
Linux Linux6256899c3a34674bba6076884aedbba49fc695e4Vendor (CNA)
Linux Linux648927ceb84021a25a0fbd5673740956f318d534Vendor (CNA)
Linux Linux7e706d50fa119eead6376bf0ef973e8d73a96030Vendor (CNA)
azl3 kernel 6.6.144.1-1 on Azure Linux 3.06.6.145.2-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:kernel5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-core5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-core5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel-matched5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules-core5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules-extra5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel-matched5.14.0-687.38.1.el9_8 · AlmaLinux:9Package registry (OSV)
debian:linux6.12.96-1 · Debian:13Package registry (OSV)
debian:linux-6.126.12.100-1~deb12u1 · Debian:12Package registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debug-devel-matched0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:kernel-debuginfo0:5.14.0-687.38.1.el9_8 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)

+3

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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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.

  • CVE-2026-533986 days apartNFSD: Fix SECINFO_NO_NAME decode error cleanup
    39Monitor
  • CVE-2026-23253129 days apartmedia: dvb-core: fix wrong reinitialization of ringbuffer on reopen
    31Monitor
  • CVE-2025-71128192 days aparterspan: Initialize options_len before referencing options.
    22Monitor
  • CVE-2025-21906480 days apartwifi: iwlwifi: mvm: clean up ROC on failure
    22Monitor

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

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-665 · Improper Initialization

CVSS vector

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

nvd-secondary

Attack context

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

ATT&CK techniques

—

Change log

  1. SSVC exploitation— → none
  2. Fix✗ → ✓

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

References

Show all references (4 more)

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

All records