boxscore/security
CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2021-47383HIGH
Linux Linux — tty: Fix out-of-bound vmalloc access in imageblit
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  H  N  H    7.1   .0027   18.5     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 –  —
  Linux    2.6.12 –                                    4.4.286
TIMELINE
  May 21  Reserved by Linux
  May 21  Published (CNA: Linux)
  Aug 4   RESCORED — CVE-2021-47383 (Linux). CVSS 7.8 → 7.1 (NVD).
CWE-125 · CNA: Linux · CVSS v3.1 · 8 references · NVD status: Modified

Description

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.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
May 21, 2024ReservedReserved by Linux
May 21, 2024PublishedPublished (CNA: Linux)
August 4, 2026RESCOREDRESCORED — CVE-2021-47383 (Linux). CVSS 7.8 → 7.1 (NVD).

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
LinuxLinux2.6.124.4.286

Weaknesses

CWE-125

References (8)

Related

Authoritative record: CVE-2021-47383 at cve.org

Vendors: linux

Weaknesses: CWE-125

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-47383 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.