How severe is CVE-2021-4155?

CVE-2021-4155 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 high, integrity none, and availability none.

Is CVE-2021-4155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4155?

CVE-2021-4155 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4155?

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

When was CVE-2021-4155 published?

CVE-2021-4155 was published on 2022-08-24 and last updated on 2026-06-17.

CVE-2021-4155

CVE-2021-4155 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-131.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-131
Affected product: Linux Linux Kernel
Published: 2022-08-24
Last modified: 2026-06-17

Description

A data leak flaw was found in the way XFS_IOC_ALLOCSP IOCTL in the XFS filesystem allowed for size increase of files with unaligned size. A local attacker could use this flaw to leak data on the XFS filesystem otherwise not accessible to them.

Frequently asked questions

What is CVE-2021-4155?: A data leak flaw was found in the way XFS_IOC_ALLOCSP IOCTL in the XFS filesystem allowed for size increase of files with unaligned size. A local attacker could use this flaw to leak data on the XFS filesystem otherwise not accessible to them.
How severe is CVE-2021-4155?: CVE-2021-4155 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 high, integrity none, and availability none.
Is CVE-2021-4155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4155?: CVE-2021-4155 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4155 published?: CVE-2021-4155 was published on 2022-08-24 and last updated on 2026-06-17.

References

Affected products (1)

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

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