Vulnerability · Published Jun 18, 2026 · Assigned by GitHub_M
CVE-2026-44663OpenEXR: Integer overflow in the HTJ2K decoder leads to heap-buffer-overflow
Medium 6.1
In plain English
A medium-severity integer overflow in openexr from AcademySoftwareFoundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions 3.4.0 through 3.4.11, an integer overflow in ht_undo_impl() in src/lib/OpenEXRCore/internal_ht.cpp leads to a heap-buffer overflow when decoding a crafted HTJ2K-compressed EXR file. decode->channels[i].width (int32_t) is multiplied by bytes_per_element in 32-bit signed arithmetic. With large widths (e.g., >= 536870912 for FLOAT data), this overflows, producing a corrupted offset that is later used for pointer arithmetic and can cause a heap out-of-bounds write. The same unchecked multiplication pattern appears in two other HTJ2K paths (bytes-per-line accumulation and pixel-line pointer advancement). As with related CVE-2026-34378 through CVE-2026-34589 fixes in other codecs, validating only after the multiplication is too late because the value may already be overflowed. This issue has been fixed in version 3.4.12.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | openexr | 3.4.13-r0 | ALPINE-CVE-2026-44663 |
| Alpine:v3.24 | openexr | 3.4.13-r0 | ALPINE-CVE-2026-44663 |
| Debian:14 | openexr | 3.4.14-0.1 | DEBIAN-CVE-2026-44663 |
| Ubuntu:25.10 | openexr | no fix listed | UBUNTU-CVE-2026-44663 |
| Ubuntu:26.10 | openexr | no fix listed | UBUNTU-CVE-2026-44663 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| AcademySoftwareFoundation | openexr | >= 3.4.0, < 3.4.11 |
Weakness: CWE-190, CWE-787 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H