How severe is CVE-2026-23109?

CVE-2026-23109 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-2026-23109 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-2026-23109?

CVE-2026-23109 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-23109?

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

Does CVE-2026-23109 have an EU (EUVD) identifier?

Yes. CVE-2026-23109 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5432.

When was CVE-2026-23109 published?

CVE-2026-23109 was published on 2026-02-04 and last updated on 2026-06-17.

CVE-2026-23109

CVE-2026-23109 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-835.

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-2026-5432
Weakness: CWE-835
Affected product: Linux Linux Kernel
Published: 2026-02-04
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes() Above the while() loop in wait_sb_inodes(), we document that we must wait for all pages under writeback for data integrity. Consequently, if a mapping, like fuse, traditionally does not have data integrity semantics, there is no need to wait at all; we can simply skip these inodes. This restores fuse back to prior behavior where syncs are no-ops. This fixes a user regression where if a system is running a faulty fuse server that does not reply to issued write requests, this causes wait_sb_inodes() to wait forever.

Frequently asked questions

What is CVE-2026-23109?: In the Linux kernel, the following vulnerability has been resolved: fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes() Above the while() loop in wait_sb_inodes(), we document that we must wait for all pages under writeback for data integrity. Consequently, if a mapping, like fuse, traditionally does not have data integrity semantics, there is no need to wait at all; we can simply skip these inodes. This restores fuse back to prior behavior where syncs are no-ops. This fixes a user regression where if a system is running a faulty fuse server that does not reply to issued write requests, this causes wait_sb_inodes() to wait forever.
How severe is CVE-2026-23109?: CVE-2026-23109 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-2026-23109 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-2026-23109?: CVE-2026-23109 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-23109?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-23109 have an EU (EUVD) identifier?: Yes. CVE-2026-23109 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5432.
When was CVE-2026-23109 published?: CVE-2026-23109 was published on 2026-02-04 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
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:rc6:*:*:*:*:*:*

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