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CVE-2022-50221

HIGHCVSS 7.1/10EPSS 0.18%

Last modified

CVE-2022-50221 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: Fix out-of-bounds access Clip memory range to screen-buffer size to avoid out-of-bounds access in fbdev deferred I/O's damage handling. Fbdev's deferred I/O can only track pages. From the range of pages, the damage handler computes the clipping rectangle for the display update. If the fbdev screen buffer ends near the beginning of a page, that page could contain more scanlines. EPSS estimates a 0.18% chance of exploitation in the next 30 days.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: Fix out-of-bounds access Clip memory range to screen-buffer size to avoid out-of-bounds access in fbdev deferred I/O's damage handling. Fbdev's deferred I/O can only track pages. From the range of pages, the damage handler computes the clipping rectangle for the display update. If the fbdev screen buffer ends near the beginning of a page, that page could contain more scanlines. The damage handler would then track these non-existing scanlines as dirty and provoke an out-of-bounds access during the screen update. Hence, clip the maximum memory range to the size of the screen buffer. While at it, rename the variables min/max to min_off/max_off in drm_fb_helper_deferred_io(). This avoids confusion with the macros of the same name.

Metrics

CVSS 3.1
7.1/10

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

EPSS Probability
0.18%

7.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
LinuxLinux Kernel>= 5.18, < 5.19.2

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2022-50221?
In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: Fix out-of-bounds access Clip memory range to screen-buffer size to avoid out-of-bounds access in fbdev deferred I/O's damage handling. Fbdev's deferred I/O can only track pages. From the range of pages, the damage handler computes the clipping rectangle for the display update. If the fbdev screen buffer ends near the beginning of a page, that page could contain more scanlines. The damage handler would then track these non-existing scanlines as dirty and provoke an out-of-bounds access during the screen update. Hence, clip the maximum memory range to the size of the screen buffer. While at it, rename the variables min/max to min_off/max_off in drm_fb_helper_deferred_io(). This avoids confusion with the macros of the same name.
How severe is CVE-2022-50221?
CVE-2022-50221 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.18% probability of exploitation in the next 30 days.
How do I fix CVE-2022-50221?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-50221?

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Source: NVD / NIST