CVE-2026-72046: gve: fix header buffer corruption with header-split and HW-GRO

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of 29 Oct 2026. If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?

0.6%

EPSS score, percentile 50.3 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

9.8 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• 6.9

Unaffected before 6.9; 6.12.101; 6.18.40; 7.1.5; 7.2

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 29 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of 29 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

As listed in the CVE record.

Versions not listed are: unaffected.

Versions not listed are: affected.

Versions the record lists as unaffected: 6.12.101, 6.18.40, 7.1.5, 7.2.

Source: CVE List, as of 29 Oct 2026. About the data.

About this vulnerability

In the Linux kernel, the following vulnerability has been resolved: gve: fix header buffer corruption with header-split and HW-GRO The DQO RX datapath programs a per-buffer-queue-descriptor header_buf_addr at post time and reads the split header back at completion time. Both the post and the read currently index the header buffer by queue position rather than by the buffer's identity: - post…

Summary: CVE record, as of 29 Oct 2026.

• CISA has not added CVE-2026-72046 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
• The CVE record was published on 15 Aug 2026.
• The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.6% (percentile 50.3), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; CVE List, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026. About the data.

Description

gve: fix header buffer corruption with header-split and HW-GRO

In the Linux kernel, the following vulnerability has been resolved: gve: fix header buffer corruption with header-split and HW-GRO The DQO RX datapath programs a per-buffer-queue-descriptor header_buf_addr at post time and reads the split header back at completion time. Both the post and the read currently index the header buffer by queue position rather than by the buffer's identity: - post (gve_rx_post_buffers_dqo): header_buf_addr is computed from bufq->tail - read (gve_rx_dqo): the header is read from desc_idx (the completion queue head index) This relies on the buffer-queue index and the completion-queue index being equal for the start of every packet, i.e. on the device consuming posted buffers and returning completions in the exact same order. That assumption does not hold once HW-GRO is enabled with multiple flows: coalesced segments are accepted and completed in an order that may differ from the order buffers were posted, and segments from different flows may interleave. That results in two problems: 1. Wrong header slot on read. Because the read offset is derived from the completion index (desc_idx) while the device wrote the header to the address programmed for the buffer's buf_id, the driver can copy a header belonging to a different packet. This shows up as throughput drop (about 30% drop and large numbers of TCP retransmissions) with header-split and HW-GRO both enabled and many streams. 2. Header buffer reused while still owned by the device. The driver advances bufq->head by one per completion and re-posts buffers based on that. Arrival of N RX completions only guarantees that at least N RX buffer descriptors have been read by the device. It does not guarantee that the device has relinquished the ownership of all the buffers corresponding to those N descriptors. With out-of-order completions (e.g. the completion for a packet copied into buffer N arrives before the completion for a packet copied into buffer N-1), the driver can re-post and overwrite a header buffer that the device is still going to write into, corrupting the header of a packet whose completion has not yet been processed. Fix both issues by indexing the header buffer by buf_id on both the post and read paths. Reading from buf_id's slot is therefore always correct regardless of completion ordering (fixes problem 1). Indexing by buf_id also ties each header slot to the lifetime of its buffer state. A buffer state is only returned to the free/recycle lists when its own completion (buf_id) is processed, so its header slot can only be re-posted after the device is done with it. This makes header slot reuse safe under out-of-order completions (fixes problem 2). Allocate (gve_rx_alloc_hdr_bufs) and free (gve_rx_free_hdr_bufs) the header buffers based on num_buf_states to match the buf_id indexing.

Source: CVE List, as of 29 Oct 2026. About the data.

Timeline

Known exploited Linux vulnerabilities

• CVE-2026-46300: Linux Kernel Missing Initialization of a Variable Vulnerability (added 28 Oct 2026)
• CVE-2025-39682: Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability (added 18 Sep 2026)
• CVE-2025-39964: Linux Kernel Race Condition Vulnerability (added 18 Sep 2026)
• CVE-2026-53266: Linux Kernel Out-of-Bounds Write Vulnerability (added 18 Sep 2026)
• CVE-2026-53362: Linux Kernel Unspecified Vulnerability (added 27 Aug 2026)