How severe is CVE-2021-47055?

CVE-2021-47055 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-2021-47055 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47055?

CVE-2021-47055 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47055?

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

Does CVE-2021-47055 have an EU (EUVD) identifier?

Yes. CVE-2021-47055 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33703.

When was CVE-2021-47055 published?

CVE-2021-47055 was published on 2024-02-29 and last updated on 2026-06-17.

CVE-2021-47055

CVE-2021-47055 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-667.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33703
Weakness: CWE-667
Affected product: Linux Linux Kernel
Published: 2024-02-29
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: mtd: require write permissions for locking and badblock ioctls MEMLOCK, MEMUNLOCK and OTPLOCK modify protection bits. Thus require write permission. Depending on the hardware MEMLOCK might even be write-once, e.g. for SPI-NOR flashes with their WP# tied to GND. OTPLOCK is always write-once. MEMSETBADBLOCK modifies the bad block table.

Frequently asked questions

What is CVE-2021-47055?: In the Linux kernel, the following vulnerability has been resolved: mtd: require write permissions for locking and badblock ioctls MEMLOCK, MEMUNLOCK and OTPLOCK modify protection bits. Thus require write permission. Depending on the hardware MEMLOCK might even be write-once, e.g. for SPI-NOR flashes with their WP# tied to GND. OTPLOCK is always write-once. MEMSETBADBLOCK modifies the bad block table.
How severe is CVE-2021-47055?: CVE-2021-47055 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-2021-47055 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47055?: CVE-2021-47055 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47055?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47055 have an EU (EUVD) identifier?: Yes. CVE-2021-47055 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33703.
When was CVE-2021-47055 published?: CVE-2021-47055 was published on 2024-02-29 and last updated on 2026-06-17.

References

Affected products (1)

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

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