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PatchSiren cyber security CVE debrief

CVE-2026-64125 Linux CVE debrief

The Linux kernel was vulnerable to a bug in the bcmgenet driver that could cause RX traffic to stop flowing while the link stays up. This issue has been resolved. The vulnerability affected the GENET hardware and was triggered when MAC EEE became active. The fix ensures that RBUF_EEE_EN and RBUF_PM_EN remain disabled across resets, preventing the RX path from breaking.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-19
Original CVE updated
2026-07-19
Advisory published
2026-07-19
Advisory updated
2026-07-19

Who should care

Users of Linux kernel with bcmgenet driver, particularly those with GENET hardware, should review their kernel versions and apply the fix to prevent RX traffic from stopping. Operators, platform administrators, vulnerability management teams, and security teams should be aware of this issue and its impact.

Technical summary

The bcmgenet driver in the Linux kernel had a vulnerability where setting RBUF_EEE_EN | RBUF_PM_EN in RBUF_ENERGY_CTRL could break the RX path on GENET hardware once MAC EEE becomes active. This happened because the bits were not properly cleared during resets, causing RX traffic to stop flowing. The fix clears these bits to prevent the issue. Users with GENET hardware and Linux kernel versions prior to the fix should review their kernel versions and apply the update. The issue was reported and resolved in the Linux kernel, with evidence available in the stable kernel tree. Defenders should verify the presence of the fix and review the official advisory for affected scope and severity. Additional verification tasks include checking relevant monitoring, detection, and logs for exposed assets.

Defensive priority

Medium

Recommended defensive actions

  • Update Linux kernel to the latest version
  • Disable EEE on bcmgenet interfaces if not needed
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
  • Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance

Evidence notes

The issue was reported and resolved in the Linux kernel. The fix is available in the stable kernel tree. Evidence is limited, but defenders should verify the presence of the fix in their Linux kernel versions and review the official advisory for affected scope and severity.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-19T16:17:54.130Z and has not been modified since then.