How severe is CVE-2025-21736?

CVE-2025-21736 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-2025-21736 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21736?

CVE-2025-21736 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-21736?

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

Does CVE-2025-21736 have an EU (EUVD) identifier?

Yes. CVE-2025-21736 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5178.

When was CVE-2025-21736 published?

CVE-2025-21736 was published on 2025-02-27 and last updated on 2026-06-17.

CVE-2025-21736

CVE-2025-21736 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-190.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-5178
Weakness: CWE-190
Affected product: Linux Linux Kernel
Published: 2025-02-27
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix possible int overflows in nilfs_fiemap() Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result by being prepared to go through potentially maxblocks == INT_MAX blocks, the value in n may experience an overflow caused by left shift of blkbits. While it is extremely unlikely to occur, play it safe and cast right hand expression to wider type to mitigate the issue. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.

Frequently asked questions

What is CVE-2025-21736?: In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix possible int overflows in nilfs_fiemap() Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result by being prepared to go through potentially maxblocks == INT_MAX blocks, the value in n may experience an overflow caused by left shift of blkbits. While it is extremely unlikely to occur, play it safe and cast right hand expression to wider type to mitigate the issue. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.
How severe is CVE-2025-21736?: CVE-2025-21736 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-2025-21736 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21736?: CVE-2025-21736 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-21736?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21736 have an EU (EUVD) identifier?: Yes. CVE-2025-21736 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5178.
When was CVE-2025-21736 published?: CVE-2025-21736 was published on 2025-02-27 and last updated on 2026-06-17.

References

Affected products (1)

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

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