CVE-2026-80779 Linux CVE debrief

Who should care

Linux kernel maintainers and users should assess exposure and prioritize patching. This includes verifying Linux kernel configurations and versions to ensure patching and assessing the exposure of Linux kernel installations to CVE-2026-80779. Linux kernel maintainers and users should also review compensating controls for exposed systems while remediation is scheduled and verified.

Why it matters

CVE-2026-80779 is a vulnerability in the Linux kernel affecting net/ionic, requiring patching and verification of Linux kernel configurations and versions.

• Verify Linux kernel configurations and versions to ensure patching
• Assess exposure of Linux kernel installations to CVE-2026-80779

Technical summary

The Linux kernel vulnerability CVE-2026-80779 affects net/ionic and has been resolved. The vulnerability is related to OOB TX partner lookup for hwstamp RXQ. The dedicated hardware timestamp RX queue is allocated with q->index equal to lif->ionic->nrxqs_per_lif. The normal txqcqs array only contains the regular queue pairs, so using that index to set rxq->partner can read one entry past txqcqs[] and then write through the derived pointer. Only link RX/TX partners for normal queue-pair indexes. Leave the hwstamp RX queue unpaired, and make the XDP_TX path abort cleanly if an RX queue has no TX partner.

Defensive priority

Assess Linux kernel exposure and prioritize patching.

Recommended defensive actions

• Assess exposure of Linux kernel installations to CVE-2026-80779
• Prioritize patching for affected Linux kernel versions
• Verify Linux kernel configurations and versions
• 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

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, which has been resolved in the Linux kernel. The CVE record was published on 2026-09-04T16:18:03.607Z and has not been modified since then. The vulnerability affects net/ionic and requires patching and verification of Linux kernel configurations and versions. Linux kernel maintainers and users should assess exposure and prioritize patching.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.