CVE-2026-47178CWE-787

libheif has Heap Out Of Bounds Write in unci subsystem

Medium · published July 21, 2026

CVSS v3.1
6.1
EPSS
0%
Percentile
7.5
In the wild
Unconfirmed
What it is

libheif is a HEIF and AVIF file format decoder and encoder. In versions 1.19.0 through 1.21.2, a crafted HEIF file (uncompressed `unci` codec, tiled, component-interleaved, 4:2:0) triggers a heap out-of-bounds write in libheif's uncompressed tile decoder. The write overwrites the C++ vtable pointer of an adjacent `unc_decoder_component_interleave` object; the next virtual call dispatches to an attacker-chosen address. Version 1.22.0 patches the issue.

The record
Technical detail
CVSS v3.1
6.1 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00183 · 7.5th percentile
Weakness
CWE-787 · Out-of-bounds Write
Published
2026-07-21T21:09Z
EPSS history
Timeline
  • 21 JUL 21:09Z
    libheif has Heap Out Of Bounds Write in unci subsystem
    cvelistv5