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Review reviewHigh

CVE-2021-47338

Linux Linux, linux kernel

In the Linux kernel, the following vulnerability has been resolved: fbmem: Do not delete the mode that is still in use The execution of fb_delete_videomode() is not based on the result of the previous fbcon_mode_deleted(). As a result, the mode is directly deleted, regardless of whether it is still in use, which may cause UAF. ================================================================== BUG: KASAN: use-after-free in fb_mode_is_equal+0x36e/0x5e0 \ drivers/video/fbdev/core/modedb.c:924 Read of size 4 at addr ffff88807e0ddb1c by task syz-executor.0/18962 CPU: 2 PID: 18962 Comm: syz-execu...

CVSS
7.8
EPSS
0.27%
18.6% percentile
CISA KEV
Not listed
Published
2024.05.22
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.27%
Technical severityCVSS 7.8

Vulnerability overview

In the Linux kernel, the following vulnerability has been resolved: fbmem: Do not delete the mode that is still in use The execution of fb_delete_videomode() is not based on the result of the previous fbcon_mode_deleted(). As a result, the mode is directly deleted, regardless of whether it is still in use, which may cause UAF. ================================================================== BUG: KASAN: use-after-free in fb_mode_is_equal+0x36e/0x5e0 \ drivers/video/fbdev/core/modedb.c:924 Read of size 4 at addr ffff88807e0ddb1c by task syz-executor.0/18962 CPU: 2 PID: 18962 Comm: syz-execu...

Affected product and versions

Product
Linux Linux, linux kernel
Affected versions
>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 359311b85ebec7c07c3a08ae2f3def946cad33fa, >= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 087bff9acd2ec6db3f61aceb3224bde90fe0f7f8, >= 13ff178ccd6d3b8074c542a911300b79c4eec255 < f193509afc7ff37a46862610c93b896044d5b693, >= 13ff178ccd6d3b8074c542a911300b79c4eec255 < d6e76469157d8f240e5dec6f8411aa8d306b1126, >= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 0af778269a522c988ef0b4188556aba97fb420cc, >= 5.3, >= 5.3 < 5.4.134, >= 5.5 < 5.10.52, >= 5.11 < 5.12.19, >= 5.13 < 5.13.4, 5.14
Fixed versions
5.4.134, 5.10.52, 5.12.19, 5.13.4

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux Linux, linux kernel and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-416