CVE-2026-64056: net: ethernet: cortina: Make RX SKB per-port

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-19 · updated 2026-09-02

Description

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: cortina: Make RX SKB per-port The SKB used to assemble packets from fragments in gmac_rx() is static local, but the Gemini has two ethernet ports, meaning there can be races between the ports on a bad day if a device is using both. Make the RX SKB a per-port variable and carry it over between invocations in the port struct instead. Zero the pointer once we call napi_gro_frags(), on error (after calling napi_free_frags()) or if the port is stopped. Zero it in some place where not strictly necessary just to emphasize what is going on. This was found by Sashiko during normal patch review.

Affected products

Linux kernel: from 4.16 before 5.10.258; from 5.11 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.142; from 6.7 before 6.12.92; from 6.13 before 6.18.34 — fixed in 5.10.258, 5.15.209, 6.1.175, 6.12.92, 6.18.34, 6.6.142

How to fix

Upgrade to a fixed version: Linux kernel 5.10.258, 5.15.209, 6.1.175, 6.12.92. Check the vendor advisory for mitigations.

References

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