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.
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).
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
| Date | Event | Detail |
| May 21, 2024 | Reserved | Reserved by Linux |
| May 21, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2021-47383 (Linux). CVSS 7.8 → 7.1 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | — |
| Linux | Linux | — | 2.6.12 | 4.4.286 |
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.