CVE-2009-4021

CVE-2009-4021 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 2.0 base score of 4.9. 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-399.

Key facts

Description

The fuse_direct_io function in fs/fuse/file.c in the fuse subsystem in the Linux kernel before 2.6.32-rc7 might allow attackers to cause a denial of service (invalid pointer dereference and OOPS) via vectors possibly related to a memory-consumption attack.

Frequently asked questions

What is CVE-2009-4021?
The fuse_direct_io function in fs/fuse/file.c in the fuse subsystem in the Linux kernel before 2.6.32-rc7 might allow attackers to cause a denial of service (invalid pointer dereference and OOPS) via vectors possibly related to a memory-consumption attack.
How severe is CVE-2009-4021?
CVE-2009-4021 has a CVSS 2.0 base score of 4.9, rated medium severity.
Is CVE-2009-4021 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4021?
CVE-2009-4021 primarily affects Linux Linux Kernel. In total, 335 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-4021?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-4021 published?
CVE-2009-4021 was published on 2009-11-25 and last updated on 2026-06-16.

References

Affected products (335)

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