CVE-2026-64055
A critical flaw in the Linux kernel’s Ethernet driver caused packet assembly to be interrupted, potentially leading to data corruption. The flaw was fixed by moving the fragment counter into the port structure so it persists across poll cycles. Users should update their kernel to a version that includes this fix.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Linux kernel, specifically the cortina Ethernet driver (gmac_rx) in the net: ethernet: cortina subsystem. Affected users are those running kernel versions before the fix.
Real-world impact
An attacker could disrupt network traffic or cause data corruption by exploiting the incomplete packet assembly, potentially leading to denial of service or other network issues.
Why this severity
The CVSS score of 9.8 reflects the vulnerability’s high impact on confidentiality, integrity, and availability, with no authentication or user interaction required, making it exploitable remotely by any attacker.
What to do about it
- 01Identify the current kernel version you are running.
- 02Update the kernel to a version that includes the fix for the cortina Ethernet driver.
- 03Reboot the system to load the updated kernel.
NVD description indicates the issue has been resolved.
Timeline
- Jul 19, 2026 · 14d agoPublishedDisclosed and added to the National Vulnerability Database.
- Jul 20, 2026 · 13d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.
- Jul 30, 2026 · 3d agoAdvisory updatedThe NVD record was last revised.
How it’s attacked
References & advisories
- git.kernel.org/stable/c/46806096f35b8d3dfa…
- git.kernel.org/stable/c/7123cf481e21b54eb6…
- git.kernel.org/stable/c/75105fcf73f1ce7d9f…
- git.kernel.org/stable/c/78cf08b3be47c28f07…
- git.kernel.org/stable/c/7af1fabdee744b7995…
- git.kernel.org/stable/c/c373b34877afea61c8…
- git.kernel.org/stable/c/df31e3b64455293df1…
- git.kernel.org/stable/c/ebd8ec2b309e3a4478…