CVE-2026-23386
MediumIn the Linux kernel, the following vulnerability has been resolved: gve: fix incorrect buffer cleanup in gve_tx_clean_pending_packets for QPL In DQ-QPL mode, gve_tx_clean_pending_packets() incorrectly uses the RDA buffer cleanup path. It iterates num_bufs times and attempts to unmap entries in the dma array. This leads to two issues: 1. The dma array shares storage with tx_qpl_buf_ids (union). Interpreting buffer IDs as DMA addresses results in attempting to unmap incorrect memory locations. 2. num_bufs in QPL mode (counting 2K chunks) can significantly exceed the size of the dma array, causing out-of-bounds access warnings (trace below is how we noticed this issue). UBSAN: array-index-out-of-bounds in drivers/net/ethernet/drivers/net/ethernet/google/gve/gve_tx_dqo.c:178:5 index 18 is out of range for type 'dma_addr_t[18]' (aka 'unsigned long long[18]') Workqueue: gve gve_service_task [gve] Call Trace: <TASK> dump_stack_lvl+0x33/0xa0 __ubsan_handle_out_of_bounds+0xdc/0x110 gve_tx_stop_ring_dqo+0x182/0x200 [gve] gve_close+0x1be/0x450 [gve] gve_reset+0x99/0x120 [gve] gve_service_task+0x61/0x100 [gve] process_scheduled_works+0x1e9/0x380 Fix this by properly checking for QPL mode and delegating to gve_free_tx_qpl_bufs() to reclaim the buffers.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected versions
Linux kernel versions
6.6
and later are affected. Fixed in
6.6.130,
6.12.78,
6.18.17,
6.19.7,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-23386 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/07e0c80e17ef781799e7cd5c41a7bf44f1bf6a5f
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PatchKernel patch commithttps://git.kernel.org/stable/c/3744ebd8ffaa542ae8110fb449adcac0202f4cc8
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PatchKernel patch commithttps://git.kernel.org/stable/c/71511dae56a75ce161aa746741e5c498feaea393
Frequently asked questions
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What is CVE-2026-23386?
CVE-2026-23386 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.6 onward and has been patched in 6.6.130, 6.12.78, 6.18.17 and others. CVE-2026-23386 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-23386?
CVE-2026-23386 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-23386?
Yes — CVE-2026-23386 has been patched. Fixed versions include 6.6.130, 6.12.78, 6.18.17 and others. If you are running Linux kernel 6.6 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23386 actively exploited?
No — CVE-2026-23386 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.