CVE-2026-64055
Linux Kernel vulnerability
- Published19 Jul 2026
Description
In the Linux kernel, the following vulnerability has been resolved: net: ethernet: cortina: Carry over frag counter The gmac_rx() NAPI poll function assembles packets in an SKB from a ring buffer. If the ring buffer gets completely emptied during a poll cycle, we exit gmac_rx(), but the packet is not yet completely assembled in the SKB, yet the fragment counter frag_nr is reset to zero on the next invocation. Solve this by making the RX fragment counter a part of the port struct, and carry it over between invocations. Reset the fragment counter only right after calling napi_gro_frags(), on error (after calling napi_free_frags()) or if stopping the port. Reset it in some place where not strictly necessary just to emphasize what is going on. This was found by Sashiko during normal patch review.
CVSS 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HAffected products
Remediation
- https://git.kernel.org/stable/c/46806096f35b8d3dfa2f321ddd77f597edcdb85f
- https://git.kernel.org/stable/c/7123cf481e21b54eb6adc4cb0d8dc2876aeaee41
- https://git.kernel.org/stable/c/75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0
- https://git.kernel.org/stable/c/78cf08b3be47c28f07008a76c932bad7cdffa9d8
- https://git.kernel.org/stable/c/7af1fabdee744b7995fe01b30b77dfc397657cb5
- https://git.kernel.org/stable/c/c373b34877afea61c89e0dd2e38948c624249b9b
References
- https://git.kernel.org/stable/c/46806096f35b8d3dfa2f321ddd77f597edcdb85f
- https://git.kernel.org/stable/c/7123cf481e21b54eb6adc4cb0d8dc2876aeaee41
- https://git.kernel.org/stable/c/75105fcf73f1ce7d9f769aaefec6e6d6645d5ac0
- https://git.kernel.org/stable/c/78cf08b3be47c28f07008a76c932bad7cdffa9d8
- https://git.kernel.org/stable/c/7af1fabdee744b7995fe01b30b77dfc397657cb5
- https://git.kernel.org/stable/c/c373b34877afea61c89e0dd2e38948c624249b9b
- https://git.kernel.org/stable/c/df31e3b64455293df1ea89c7da7d5c9bfbcdd253
- https://git.kernel.org/stable/c/ebd8ec2b309e3a447851b456ccaf8fb39f3661e7
Frequently asked
Is CVE-2026-64055 being actively exploited?
CVE-2026-64055 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.51%.
How severe is CVE-2026-64055?
CVE-2026-64055 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.51% probability of exploitation.
Which products are affected by CVE-2026-64055?
Affected products include Linux Kernel.
How do I fix CVE-2026-64055?
Upgrade affected software to a fixed version, for example Linux Kernel 5.10.258 or later, then confirm no affected versions remain in your inventory.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-64055 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.