CVE-2026-34588CWE-125CWE-190CWE-787

OpenEXR has a signed 32-bit Overflow in PIZ Decoder Leads to OOB Read/Write

High · published April 6, 2026

CVSS v4.0
8.6
EPSS
1%
Percentile
46.3
In the wild
Unconfirmed
What it is

OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.1.0 to before 3.2.7, 3.3.9, and 3.4.9, internal_exr_undo_piz() advances the working wavelet pointer with signed 32-bit arithmetic. Because nx, ny, and wcount are int, a crafted EXR file can make this product overflow and wrap. The next channel then decodes from an incorrect address. The wavelet decode path operates in place, so this yields both out-of-bounds reads and out-of-bounds writes. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.

The record
Technical detail
CVSS v4.0
8.6 · HIGH
Vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00567 · 46.3th percentile
Weaknesses
CWE-125 · Out-of-bounds Read; CWE-190 · Integer Overflow or Wraparound; CWE-787 · Out-of-bounds Write
Published
2026-04-06T15:31Z
EPSS history
Timeline
  • 06 APR 15:31Z
    OpenEXR has a signed 32-bit Overflow in PIZ Decoder Leads to OOB Read/Write
    cvelistv5