How severe is CVE-2026-23261?

CVE-2026-23261 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-23261 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-23261?

CVE-2026-23261 primarily affects Linux Linux Kernel. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-23261?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-23261 have an EU (EUVD) identifier?

Yes. CVE-2026-23261 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12896.

When was CVE-2026-23261 published?

CVE-2026-23261 was published on 2026-03-18 and last updated on 2026-06-17.

CVE-2026-23261

CVE-2026-23261 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-12896
Weakness: CWE-401
Affected product: Linux Linux Kernel
Published: 2026-03-18
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: nvme-fc: release admin tagset if init fails nvme_fabrics creates an NVMe/FC controller in following path: nvmf_dev_write() -> nvmf_create_ctrl() -> nvme_fc_create_ctrl() -> nvme_fc_init_ctrl() nvme_fc_init_ctrl() allocates the admin blk-mq resources right after nvme_add_ctrl() succeeds. If any of the subsequent steps fail (changing the controller state, scheduling connect work, etc.), we jump to the fail_ctrl path, which tears down the controller references but never frees the admin queue/tag set. The leaked blk-mq allocations match the kmemleak report seen during blktests nvme/fc. Check ctrl->ctrl.admin_tagset in the fail_ctrl path and call nvme_remove_admin_tag_set() when it is set so that all admin queue allocations are reclaimed whenever controller setup aborts.

Frequently asked questions

What is CVE-2026-23261?: In the Linux kernel, the following vulnerability has been resolved: nvme-fc: release admin tagset if init fails nvme_fabrics creates an NVMe/FC controller in following path: nvmf_dev_write() -> nvmf_create_ctrl() -> nvme_fc_create_ctrl() -> nvme_fc_init_ctrl() nvme_fc_init_ctrl() allocates the admin blk-mq resources right after nvme_add_ctrl() succeeds. If any of the subsequent steps fail (changing the controller state, scheduling connect work, etc.), we jump to the fail_ctrl path, which tears down the controller references but never frees the admin queue/tag set. The leaked blk-mq allocations match the kmemleak report seen during blktests nvme/fc. Check ctrl->ctrl.admin_tagset in the fail_ctrl path and call nvme_remove_admin_tag_set() when it is set so that all admin queue allocations are reclaimed whenever controller setup aborts.
How severe is CVE-2026-23261?: CVE-2026-23261 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-23261 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-23261?: CVE-2026-23261 primarily affects Linux Linux Kernel. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-23261?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-23261 have an EU (EUVD) identifier?: Yes. CVE-2026-23261 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12896.
When was CVE-2026-23261 published?: CVE-2026-23261 was published on 2026-03-18 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.18:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.18:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*

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