CVE-2026-53106

bpf: Do not allow deleting local storage in NMI

Published Jun 24, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

bpf: Do not allow deleting local storage in NMI

Currently, local storage may deadlock when deferring freeing selem or
local storage through kfree_rcu(), call_rcu() or call_rcu_tasks_trace()
in NMI or reentrant. Since deleting selem in NMI is an unlikely use
case, partially mitigate it by returning error when calling from
bpf_xxx_storage_delete() helpers in NMI. Note that, it is still possible
to deadlock through reentrant. A full mitigation requires returning
error when irqs_disabled() is true, which, however is too heavy-handed
for bpf_xxx_storage_delete().

The long-term solution requires _nolock versions of call_rcu. Another
possible solution is to defer the free through irq_work [0], but it
would grow the size of selem, which is non-ideal.

The check is only needed in bpf_selem_unlink(), which is used by helpers
and syscalls. bpf_selem_unlink_nofail() is fine as it is called during
map and owner tear down that never run in NMI or reentrant.

[0] https://lore.kernel.org/bpf/20260205190233.912-1-alexei.starovoitov@gmail.com/

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8566-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8568-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8569-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-8593-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8603-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8618-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8663-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8664-1 Linux kernel (NVIDIA BaseOS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-3 Linux kernel (Oracle) vulnerabilities
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-400
Type Values Removed Values Added
Weaknesses CWE-833
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Type Values Removed Values Added
Weaknesses CWE-400
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: bpf: Do not allow deleting local storage in NMI Currently, local storage may deadlock when deferring freeing selem or local storage through kfree_rcu(), call_rcu() or call_rcu_tasks_trace() in NMI or reentrant. Since deleting selem in NMI is an unlikely use case, partially mitigate it by returning error when calling from bpf_xxx_storage_delete() helpers in NMI. Note that, it is still possible to deadlock through reentrant. A full mitigation requires returning error when irqs_disabled() is true, which, however is too heavy-handed for bpf_xxx_storage_delete(). The long-term solution requires _nolock versions of call_rcu. Another possible solution is to defer the free through irq_work [0], but it would grow the size of selem, which is non-ideal. The check is only needed in bpf_selem_unlink(), which is used by helpers and syscalls. bpf_selem_unlink_nofail() is fine as it is called during map and owner tear down that never run in NMI or reentrant. [0] https://lore.kernel.org/bpf/20260205190233.912-1-alexei.starovoitov@gmail.com/
Title bpf: Do not allow deleting local storage in NMI
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Nov 6, 2026, 4:24 PM
Reserved
Jun 9, 2026, 7:44 AM
Status
Analyzed
Published
Jun 24, 2026, 5:17 PM
Modified
Nov 6, 2026, 5:18 PM
Severity
Low
Public date
Jun 24, 2026, 12:00 AM