CVE-2026-72017

Memory exhaustion via unreleased transmit buffers

Published Aug 15, 2026 · Updated Aug 15, 2026

Memory leak in the Linux kernel MACB driver allows local users to exhaust memory by closing an interface with pending transmissions. macb_free_consistent() frees queue->tx_skb without first releasing in-flight socket buffers stored in its entries. Triggering cleanup requires authority to close a MACB network interface; repeated cycles can deplete kernel memory and disrupt service.

CVSS severity5.5
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in the Linux kernel MACB driver allows local users to exhaust memory by closing an interface with pending transmissions. macb_free_consistent() frees queue->tx_skb without first releasing in-flight socket buffers stored in its entries. Triggering cleanup requires authority to close a MACB network interface; repeated cycles can deplete kernel memory and disrupt service.

The record

CVE
CVE-2026-72017
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.6.20
  2. Affected versionversion=89e5785fc8a6b9eafd37f2318a9a76d479c796be <109241d9880488aafd8e104832b4d4859ad57244
  3. Affected versionversion=89e5785fc8a6b9eafd37f2318a9a76d479c796be <2143fdc0ce27adbb1caaa1a97e0bfb9f3750aef4
  4. Affected versionversion=89e5785fc8a6b9eafd37f2318a9a76d479c796be <26b131b2d5b55a81ef6182769d28105a870c0eb2
  5. Affected versionversion=89e5785fc8a6b9eafd37f2318a9a76d479c796be <27f575836cfebbf872dec020428742b10650a955
  6. Affected versionversion=89e5785fc8a6b9eafd37f2318a9a76d479c796be <6124bd785073659c99385094657b77382ebce11b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.20; version=89e5785fc8a6b9eafd37f2318a9a76d479c796be <109241d9880488aafd8e104832b4d4859ad57244; version=89e5785fc8a6b9eafd37f2318a9a76d479c796be <2143fdc0ce27adbb1caaa1a97e0bfb9f3750aef4; version=89e5785fc8a6b9eafd37f2318a9a76d479c796be <26b131b2d5b55a81ef6182769d28105a870c0eb2; version=89e5785fc8a6b9eafd37f2318a9a76d479c796be <27f575836cfebbf872dec020428742b10650a955; version=89e5785fc8a6b9eafd37f2318a9a76d479c796be <6124bd785073659c99385094657b77382ebce11b

Published CVSS scores

2.3SUSECVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L
4.4Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
5.5Oracle LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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