7.1
/ 10
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Description
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.2.0 to before 3.2.7, 3.3.9, and 3.4.9, a misaligned memory write vulnerability exists in LossyDctDecoder_execute() in src/lib/OpenEXRCore/internal_dwa_decoder.h:749. When decoding a DWA or DWAB-compressed EXR file containing a FLOAT-type channel, the decoder performs an in-place HALF→FLOAT conversion by casting an unaligned uint8_t * row pointer to float * and writing through it. Because the row buffer may not be 4-byte aligned, this constitutes undefined behavior under the C standard and crashes immediately on architectures that enforce alignment (ARM, RISC-V, etc.). On x86 it is silently tolerated at runtime but remains exploitable via compiler optimizations that assume aligned access. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.
Basic Information
ID
CVE-2026-34379
Source
GitHub_M
Published
Apr 6, 2026 at 15:21
Modified
Apr 7, 2026 at 03:07
Affected Product
Vendor
AcademySoftwareFoundation
Product
openexr
Version
>= 3.2.0, < 3.2.7
Affected Versions
AcademySoftwareFoundation openexr >= 3.2.0, < 3.2.7
AcademySoftwareFoundation openexr >= 3.3.0, < 3.3.9
AcademySoftwareFoundation openexr >= 3.4.0, < 3.4.9
AcademySoftwareFoundation openexr >= 3.3.0, < 3.3.9
AcademySoftwareFoundation openexr >= 3.4.0, < 3.4.9