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NVD / CVE Program· CNA Linux

CVE-2026-64037: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled

Noroxi assessment

Priority: Monitor (action score 39/100)

  • 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: 0.43% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: Linux Linux 92cee08dc4f00e77fd1317e4343c5d458b0abab7, 9e360e610a73f62432e986775023d5382773f045, cbe1c8245e4469d1aa6e12e5d913611376d23788.

Low priority for now. Upgrade to Linux Linux 92cee08dc4f00e77fd1317e4343c5d458b0abab7, 9e360e610a73f62432e986775023d5382773f045, cbe1c8245e4469d1aa6e12e5d913611376d23788 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: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled When the TLC notification disables AMSDU for a TID, the MLD driver sets max_tid_amsdu_len to the sentinel value 1. The TSO segmentation path in iwl_mld_tx_tso_segment() checks for zero but not for this sentinel, allowing it to reach the num_subframes calculation: num_subframes = (max_tid_amsdu_len + pad) / (subf_len + pad) = (1 + 2) / (1534 + 2) = 0 This zero propagates to iwl_tx_tso_segment() which sets: gso_size = num_subframes * mss = 0 Calling skb_gso_segment() with gso_size=0 creates over 32000 tiny segments from a single GSO skb. This floods the TX ring with ~1024 micro-frames (the rest are purged), creating a massive burst of TX completion events that can lead to memory corruption and a subsequent use-after-free in TCP's retransmit queue (refcount underflow in tcp_shifted_skb, NULL deref in tcp_rack_detect_loss). The MVM driver is immune because it checks mvmsta->amsdu_enabled before reaching the num_subframes calculation. The MLD driver has no equivalent bitmap check and relies solely on max_tid_amsdu_len, which does not catch the sentinel value. Fix this by detecting the sentinel value (max_tid_amsdu_len == 1) at the existing check and falling back to non-AMSDU TSO segmentation. Also add a WARN_ON_ONCE guard after the num_subframes division as defense-in-depth to catch any future code paths that produce zero through a different mechanism.

CriticalCVSS 9.8 · v3.1—No exploit Fix available
Published
Jul 19, 2026
Updated
Oct 19, 2026
EPSS
0.4% · 37th percentile

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
9.8
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 kernel6.15 and later · before 6.18.34
  • linux linux kernel6.19 and later · before 7.0.11
  • linux linux kernel7.1

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

    • 6.15affected
    • d1e879ec600f9b3bdd253167533959facfefb17b and later · before 9e360e610a73f62432e986775023d5382773f045affected · git
    • d1e879ec600f9b3bdd253167533959facfefb17b and later · before cbe1c8245e4469d1aa6e12e5d913611376d23788affected · git
    • d1e879ec600f9b3bdd253167533959facfefb17b and later · before 92cee08dc4f00e77fd1317e4343c5d458b0abab7affected · git
    • before 6.15not affected · semver
    • 6.18.34 and later · up to and including 6.18.*not affected · semver
    • 7.0.11 and later · up to and including 7.0.*not affected · semver
    • 7.1 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:10kernelbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64kbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debugbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-develbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-devel-matchedbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-modulesbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-extrabefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-develbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-devel-matchedbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-modulesbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-modules-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-64k-modules-extrabefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-abi-stablelistsbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-cross-headersbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debugbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debug-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debug-develbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debug-devel-matchedbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debug-modulesbefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.el10_2
AlmaLinux:10kernel-debug-modules-corebefore 6.12.0-211.53.1.el10_26.12.0-211.53.1.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-2026-64035Jul 19, 2026 · igc: set tx buffer type for SMD frames
    39Monitor
  • ← EarlierCVE-2026-64036Jul 19, 2026 · cgroup/rstat: validate cpu before css_rstat_cpu() access
    31Monitor
  • Later →CVE-2026-64038Jul 19, 2026 · hwmon: (lm90) Stop work before releasing hwmon device
    18Monitor

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 Linux92cee08dc4f00e77fd1317e4343c5d458b0abab7Vendor (CNA)
Linux Linux9e360e610a73f62432e986775023d5382773f045Vendor (CNA)
Linux Linuxcbe1c8245e4469d1aa6e12e5d913611376d23788Vendor (CNA)
almalinux:kernel6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-core6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-core6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-devel6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-devel-matched6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-modules6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-modules-core6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-debug-modules-extra6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-devel6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
almalinux:kernel-64k-devel-matched6.12.0-211.53.1.el10_2 · AlmaLinux:10Package registry (OSV)
debian:linux7.0.12-1 · Debian:14Package registry (OSV)
red hat:kernel-64k-debug-debuginfo0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-64k-debug-devel0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-64k-debug-devel-matched0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-64k-debuginfo0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-64k-devel0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-64k-devel-matched0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debug-debuginfo0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debug-devel0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debug-devel-matched0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debuginfo0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debuginfo-common-aarch640:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:kernel-debuginfo-common-ppc64le0:6.12.0-211.53.1.el10_2 · Red Hat:enterprise_linux:10.2Package registry (OSV)
rocky linux:kernel0:6.12.0-211.53.1.el10_2 · Rocky Linux:10Package registry (OSV)

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-2026-640460 days apartnet: tls: prevent chain-after-chain in plain text SG
    39Monitor
  • CVE-2026-5322124 days apartip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()
    39Monitor
  • CVE-2026-4611552 days apartblock: add pgmap check to biovec_phys_mergeable
    39Monitor
  • CVE-2026-4311474 days apartnetfilter: nft_set_pipapo_avx2: don't return non-matching entry on expiry
    37Monitor
  • CVE-2026-641060 days apartKVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits
    36Monitor
  • CVE-2026-4626646 days apartinet: RAW sockets using IPPROTO_RAW MUST drop incoming ICMP
    36Monitor

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.
  • No special conditions are required; it is repeatable.

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
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-20 · Improper Input Validation

CVSS vector

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

Change log

  1. SSVC exploitation— → none
  2. 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