← Vulnerability feed

Vulnerability record · CVE-2026-64210 · published 24 July 2026

CVE-2026-64210: Linux kernel vulnerability

Linux · Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: xsk: Fix unlocked writing to ICOSQ During napi poll, when the affinity changes and there's still XSK work to be done, we trigger an ICOSQ interrupt on the new CPU. However, this triggering on the ICOSQ is done unprotected. There are 2 such races: A) mlx5e_trigger_irq() is called while mlx5e_xsk_alloc_rx_mpwqe() is running from a different CPU due to affinity change. This can happen because IRQ triggering is done after napi_complete_done(). At this point the NAPI can be scheduled on a different CPU. Like this: CPU A (old affinity, NAPI tail) CPU B (new affinity, fresh NAPI) ------------------------------- -------------------------------- napi_complete_done() clears SCHED mlx5e_cq_arm(...) napi_schedule_prep() sets SCHED mlx5e_napi_poll() mlx5e_xsk_alloc_rx_mpwqe() mlx5e_icosq_sync_lock() // noop memcpy 640 B UMR body advance sq->pc by 10 mlx5e_trigger_irq(&c->icosq) wqe_info[pi] = {NOP, 1} mlx5e_post_nop() advances sq->pc B) mlx5e_trigger_irq() is called on the ICOSQ when mlx5e_trigger_napi_icosq() is running. The obvious fix would be to lock the ICOSQ. But ICOSQ has an optimized locking scheme that doesn't work for this scenario. Kick the async ICOSQ instead which is always locked. This issue was noticed in the wild with the following splat: netdevice: ge-0-0-1: Bad OP in ICOSQ CQE: 0xd WARNING: drivers/net/ethernet/mellanox/mlx5/core/en_rx.c:826 [...] [...] Call Trace: <IRQ> mlx5e_napi_poll+0x11d/0x7f0 [mlx5_core] __napi_poll+0x30/0x200 ? skb_defer_free_flush+0x9c/0xc0 net_rx_action+0x2fe/0x3f0 handle_softirqs+0xd8/0x340 __irq_exit_rcu+0xbc/0xe0 common_interrupt+0x85/0xa0 </IRQ> <TASK> asm_common_interrupt+0x26/0x40 [...] ---[ end trace 0000000000000000 ]--- mlx5_core 0000:08:00.0 ge-0-0-1: Error cqe on cqn 0x548, ci 0x2022, qn 0x8f4, opcode 0xd, syndrome 0x2, vendor syndrome 0x68 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000030: 00 00 00 00 01 00 68 02 01 00 08 f4 de 14 59 d2 WQE DUMP: WQ size 16384 WQ cur size 0, WQE index 0x1e14, len: 64 00000000: 00 00 00 01 d9 ed 80 02 00 00 00 01 d9 ed 90 02 00000010: 00 00 00 01 d9 ed a0 02 00 00 00 01 d9 ed b0 02 00000020: 00 00 00 01 d9 ed c0 02 00 00 00 01 d9 ed d0 02 00000030: 00 00 00 01 d9 ed e0 02 00 00 00 01 d9 ed f0 02 mlx5_core 0000:08:00.0 ge-0-0-1: Error cqe on cqn 0x548, ci 0x2023, qn 0x8f4, opcode 0xd, syndrome 0x5, vendor syndrome 0xf9 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000030: 00 00 00 00 01 00 f9 05 01 00 08 f4 de 15 cf d2

7.5 CVSS 3.1 High EPSS 0.48% · top 61.2%
7.5CVSS 3.1 base score
0.48%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References
14 Sep 2026Last modified by NVD

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: xsk: Fix unlocked writing to ICOSQ During napi poll, when the affinity changes and there's still XSK work to be done, we trigger an ICOSQ interrupt on the new CPU. However, this triggering on the ICOSQ is done unprotected. There are 2 such races: A) mlx5e_trigger_irq() is called while mlx5e_xsk_alloc_rx_mpwqe() is running from a different CPU due to affinity change. This can happen because IRQ triggering is done after napi_complete_done(). At this point the NAPI can be scheduled on a different CPU. Like this: CPU A (old affinity, NAPI tail) CPU B (new affinity, fresh NAPI) ------------------------------- -------------------------------- napi_complete_done() clears SCHED mlx5e_cq_arm(...) napi_schedule_prep() sets SCHED mlx5e_napi_poll() mlx5e_xsk_alloc_rx_mpwqe() mlx5e_icosq_sync_lock() // noop memcpy 640 B UMR body advance sq->pc by 10 mlx5e_trigger_irq(&c->icosq) wqe_info[pi] = {NOP, 1} mlx5e_post_nop() advances sq->pc B) mlx5e_trigger_irq() is called on the ICOSQ when mlx5e_trigger_napi_icosq() is running. The obvious fix would be to lock the ICOSQ. But ICOSQ has an optimized locking scheme that doesn't work for this scenario. Kick the async ICOSQ instead which is always locked. This issue was noticed in the wild with the following splat: netdevice: ge-0-0-1: Bad OP in ICOSQ CQE: 0xd WARNING: drivers/net/ethernet/mellanox/mlx5/core/en_rx.c:826 [...] [...] Call Trace: <IRQ> mlx5e_napi_poll+0x11d/0x7f0 [mlx5_core] __napi_poll+0x30/0x200 ? skb_defer_free_flush+0x9c/0xc0 net_rx_action+0x2fe/0x3f0 handle_softirqs+0xd8/0x340 __irq_exit_rcu+0xbc/0xe0 common_interrupt+0x85/0xa0 </IRQ> <TASK> asm_common_interrupt+0x26/0x40 [...] ---[ end trace 0000000000000000 ]--- mlx5_core 0000:08:00.0 ge-0-0-1: Error cqe on cqn 0x548, ci 0x2022, qn 0x8f4, opcode 0xd, syndrome 0x2, vendor syndrome 0x68 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000030: 00 00 00 00 01 00 68 02 01 00 08 f4 de 14 59 d2 WQE DUMP: WQ size 16384 WQ cur size 0, WQE index 0x1e14, len: 64 00000000: 00 00 00 01 d9 ed 80 02 00 00 00 01 d9 ed 90 02 00000010: 00 00 00 01 d9 ed a0 02 00 00 00 01 d9 ed b0 02 00000020: 00 00 00 01 d9 ed c0 02 00 00 00 01 d9 ed d0 02 00000030: 00 00 00 01 d9 ed e0 02 00 00 00 01 d9 ed f0 02 mlx5_core 0000:08:00.0 ge-0-0-1: Error cqe on cqn 0x548, ci 0x2023, qn 0x8f4, opcode 0xd, syndrome 0x5, vendor syndrome 0xf9 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000030: 00 00 00 00 01 00 f9 05 01 00 08 f4 de 15 cf d2

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://git.kernel.org/stable/c/0c8f331485656d5937d56a488016b944a038fe2f
https://git.kernel.org/stable/c/54a97ef1025236cc1bc54d79c7ae2eb8027ce4b8
https://git.kernel.org/stable/c/8d3b91e7d81000d295cd914d4d9d6f860252e2bf Patch
https://git.kernel.org/stable/c/c326f9c68921e2f14dfcecb2f6b4216313d50248 Patch
https://git.kernel.org/stable/c/f37adef34eb7ebe29a534d20ccadd72bd7ff664e
https://git.kernel.org/stable/c/f3d8c2fd591bb603b069e151881a317e26a3f478

Track CVE-2026-64210 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2025-39682Linux kernel TLS zero-length record handling flaw on rx_listThe Linux kernel TLS receive path mishandles zero-length records that arrive from the rx_list, breaking the assumption that a record type change cann…KEVEPSS 2.9%analysed8.8CVE-2026-53266Linux kernel ebtables SNAT out-of-bounds write in ARP rewriteThe ebtables SNAT target rewrites the ARP sender hardware address via skb_store_bits() without first making that range writable. When the ARP SHA byt…KEVEPSS 0.65%analysed8.8CVE-2023-3079Google Chrome V8 type confusion enables heap corruptionCVE-2023-3079 is a type confusion flaw in the V8 JavaScript engine in Google Chrome before 114.0.5735.110. A crafted HTML page can trigger the confus…KEVEPSS 32%analysed8.8CVE-2013-6282Linux kernel ARM get_user/put_user missing address validationThe get_user and put_user API functions in the Linux kernel before 3.5.5 on v6k and v7 ARM platforms fail to validate certain addresses, allowing cra…KEVEPSS 40%analysed8.4CVE-2022-0185Linux Kernel Filesystem Context Heap Buffer OverflowThe legacy_parse_param function in the Linux kernel's Filesystem Context functionality fails to properly verify supplied parameter lengths, causing a…KEVEPSS 25%analysed8.4CVE-2013-2094Linux Kernel perf_swevent_init Integer Type Flaw Enables Local Privilege EscalationThe perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, allowing a local user to…KEVEPSS 48%analysed7.8CVE-2026-53362Linux kernel IPv6 UDP paged allocation out-of-bounds write__ip6_append_data() in the Linux kernel mis-accounts fraggap on the paged-allocation path, leaving the linear skb area undersized while pagedlen is o…KEVEPSS 0.71%analysed7.8CVE-2026-31431Linux kernel algif_aead in-place crypto operation flawThe Linux kernel's algif_aead AF_ALG AEAD interface operated in-place on buffers that come from different mappings, a flaw the fix resolves by revert…KEVEPSS 3.4%analysed

Source: NIST National Vulnerability Database (record CVE-2026-64210), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.