What is CVE-2021-47383?

CVE-2021-47383 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10, classified as a Out-of-bounds Read flaw (CWE-125). CVE-2021-47383 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47383?

CVE-2021-47383 has a CVSS score of 7.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.

Is there a patch available for CVE-2021-47383?

No patch is currently available for CVE-2021-47383. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2021-47383 actively exploited?

CVE-2021-47383 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Out-of-bounds Read (CWE-125)?

The product reads data past the end or before the beginning of the intended buffer. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/125.html

CVE-2021-47383

High

In the Linux kernel, the following vulnerability has been resolved: tty: Fix out-of-bound vmalloc access in imageblit This issue happens when a userspace program does an ioctl FBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct containing only the fields xres, yres, and bits_per_pixel with values. If this struct is the same as the previous ioctl, the vc_resize() detects it and doesn't call the resize_screen(), leaving the fb_var_screeninfo incomplete. And this leads to the updatescrollmode() calculates a wrong value to fbcon_display->vrows, which makes the real_y() return a wrong value of y, and that value, eventually, causes the imageblit to access an out-of-bound address value. To solve this issue I made the resize_screen() be called even if the screen does not need any resizing, so it will "fix and fill" the fb_var_screeninfo independently.

Package Linux Kernel

Published 2024-05-21

Last modified 2025-12-10

CVSS version 3.1

Patch available

Awaiting data

CVSS 3.1 score

7.1

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Weakness type

CWE-125

CVE-2021-47383 is a Out-of-bounds Read vulnerability

What is Out-of-bounds Read?

The product reads data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2021-47383 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/067c694d06040db6f0c65281bb358452ca6d85b9
Patch
Kernel patch commit
https://git.kernel.org/stable/c/3b0c406124719b625b1aba431659f5cdc24a982c
Patch
Kernel patch commit
https://git.kernel.org/stable/c/699d926585daa6ec44be556cdc1ab89e5d54557b
Patch

8 patch commits total View all on NVD

Details

CVE ID CVE-2021-47383

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2024-05-21

Modified 2025-12-10

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2021-47383?

CVE-2021-47383 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 , classified as an Out-of-bounds Read flaw (CWE-125) . CVE-2021-47383 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47383?

CVE-2021-47383 has a CVSS score of 7.1 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.
Is there a patch available for CVE-2021-47383?

No patch is currently available for CVE-2021-47383. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2021-47383 actively exploited?

No — CVE-2021-47383 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Out-of-bounds Read (CWE-125)?

The product reads data past the end or before the beginning of the intended buffer. View CWE-125 on MITRE CWE →