CVE-2026-23126
MediumIn the Linux kernel, the following vulnerability has been resolved: netdevsim: fix a race issue related to the operation on bpf_bound_progs list The netdevsim driver lacks a protection mechanism for operations on the bpf_bound_progs list. When the nsim_bpf_create_prog() performs list_add_tail, it is possible that nsim_bpf_destroy_prog() is simultaneously performs list_del. Concurrent operations on the list may lead to list corruption and trigger a kernel crash as follows: [ 417.290971] kernel BUG at lib/list_debug.c:62! [ 417.290983] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 417.290992] CPU: 10 PID: 168 Comm: kworker/10:1 Kdump: loaded Not tainted 6.19.0-rc5 #1 [ 417.291003] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 417.291007] Workqueue: events bpf_prog_free_deferred [ 417.291021] RIP: 0010:__list_del_entry_valid_or_report+0xa7/0xc0 [ 417.291034] Code: a8 ff 0f 0b 48 89 fe 48 89 ca 48 c7 c7 48 a1 eb ae e8 ed fb a8 ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 80 a1 eb ae e8 d9 fb a8 ff <0f> 0b 48 89 d1 48 c7 c7 d0 a1 eb ae 48 89 f2 48 89 c6 e8 c2 fb a8 [ 417.291040] RSP: 0018:ffffb16a40807df8 EFLAGS: 00010246 [ 417.291046] RAX: 000000000000006d RBX: ffff8e589866f500 RCX: 0000000000000000 [ 417.291051] RDX: 0000000000000000 RSI: ffff8e59f7b23180 RDI: ffff8e59f7b23180 [ 417.291055] RBP: ffffb16a412c9000 R08: 0000000000000000 R09: 0000000000000003 [ 417.291059] R10: ffffb16a40807c80 R11: ffffffffaf9edce8 R12: ffff8e594427ac20 [ 417.291063] R13: ffff8e59f7b44780 R14: ffff8e58800b7a05 R15: 0000000000000000 [ 417.291074] FS: 0000000000000000(0000) GS:ffff8e59f7b00000(0000) knlGS:0000000000000000 [ 417.291079] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 417.291083] CR2: 00007fc4083efe08 CR3: 00000001c3626006 CR4: 0000000000770ee0 [ 417.291088] PKRU: 55555554 [ 417.291091] Call Trace: [ 417.291096] <TASK> [ 417.291103] nsim_bpf_destroy_prog+0x31/0x80 [netdevsim] [ 417.291154] __bpf_prog_offload_destroy+0x2a/0x80 [ 417.291163] bpf_prog_dev_bound_destroy+0x6f/0xb0 [ 417.291171] bpf_prog_free_deferred+0x18e/0x1a0 [ 417.291178] process_one_work+0x18a/0x3a0 [ 417.291188] worker_thread+0x27b/0x3a0 [ 417.291197] ? __pfx_worker_thread+0x10/0x10 [ 417.291207] kthread+0xe5/0x120 [ 417.291214] ? __pfx_kthread+0x10/0x10 [ 417.291221] ret_from_fork+0x31/0x50 [ 417.291230] ? __pfx_kthread+0x10/0x10 [ 417.291236] ret_from_fork_asm+0x1a/0x30 [ 417.291246] </TASK> Add a mutex lock, to prevent simultaneous addition and deletion operations on the list.
CVSS 3.1 score
4.7
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-362CVE-2026-23126 is a Race Condition vulnerability
What is Race Condition?
The product contains a code sequence that can run concurrently with other code, creating unexpected states. Learn more on MITRE CWE
Affected versions
Linux kernel versions
4.16
and later are affected. Fixed in
6.1.162,
6.6.122,
6.12.68,
6.18.8,
6.19
and their respective stable series.
References
The following references provide additional information about CVE-2026-23126 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/3f560cfc7706029294132482fff5d1bc7884b70d
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PatchKernel patch commithttps://git.kernel.org/stable/c/68462ecc40ea8f780fb3c74ebfddd05506bb731b
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PatchKernel patch commithttps://git.kernel.org/stable/c/b97d5eedf4976cc94321243be83b39efe81a0e15
Frequently asked questions
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What is CVE-2026-23126?
CVE-2026-23126 is a Medium severity Linux kernel vulnerability with a CVSS score of 4.7 out of 10 , classified as a Race Condition flaw (CWE-362) . It affects Linux kernel versions from 4.16 onward and has been patched in 6.1.162, 6.6.122, 6.12.68 and others. CVE-2026-23126 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-2026-23126?
CVE-2026-23126 has a CVSS score of 4.7 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-23126?
Yes — CVE-2026-23126 has been patched. Fixed versions include 6.1.162, 6.6.122, 6.12.68 and others. If you are running Linux kernel 4.16 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23126 actively exploited?
No — CVE-2026-23126 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Race Condition (CWE-362)?
The product contains a code sequence that can run concurrently with other code, creating unexpected states. View CWE-362 on MITRE CWE →