CVE-2026-64055Network attack vector

Remote kernel memory corruption via fragment counter reset

Published Jul 19, 2026 · Updated Jul 19, 2026

Memory corruption in the Cortina Gemini GMAC driver in affected Linux releases allows remote attackers to corrupt kernel memory via Ethernet frames. When gmac_rx() drains the receive ring before completing an SKB, the next poll resets frag_nr to zero instead of preserving the partial packet's fragment index. Unauthenticated Ethernet traffic reaches the faulty receive path only on systems using this driver, where fragment-slot reuse corrupts kernel state or triggers a panic.

CVSS severity9.8
Critical
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in the Cortina Gemini GMAC driver in affected Linux releases allows remote attackers to corrupt kernel memory via Ethernet frames. When gmac_rx() drains the receive ring before completing an SKB, the next poll resets frag_nr to zero instead of preserving the partial packet's fragment index. Unauthenticated Ethernet traffic reaches the faulty receive path only on systems using this driver, where fragment-slot reuse corrupts kernel state or triggers a panic.

The record

CVE
CVE-2026-64055
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=4.16
  2. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <46806096f35b8d3dfa2f321ddd77f597edcdb85f
  3. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <7123cf481e21b54eb6adc4cb0d8dc2876aeaee41
  4. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0
  5. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <78cf08b3be47c28f07008a76c932bad7cdffa9d8
  6. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <7af1fabdee744b7995fe01b30b77dfc397657cb5
  7. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <c373b34877afea61c89e0dd2e38948c624249b9b
  8. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <df31e3b64455293df1ea89c7da7d5c9bfbcdd253
  9. Affected versionversion=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <ebd8ec2b309e3a447851b456ccaf8fb39f3661e7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.16; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <46806096f35b8d3dfa2f321ddd77f597edcdb85f; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <7123cf481e21b54eb6adc4cb0d8dc2876aeaee41; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <78cf08b3be47c28f07008a76c932bad7cdffa9d8; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <7af1fabdee744b7995fe01b30b77dfc397657cb5; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <c373b34877afea61c89e0dd2e38948c624249b9b; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <df31e3b64455293df1ea89c7da7d5c9bfbcdd253; version=4d5ae32f5e1e13f7f36d6439ec3257993b9f5b88 <ebd8ec2b309e3a447851b456ccaf8fb39f3661e7

Published CVSS scores

9.8LinuxCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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