CVE-2026-44663: academysoftwarefoundation openexr Integer Overflow or Wraparound

Vulnerability summary

CVE-2026-44663 is a high (CVSS 7.1) Integer Overflow or Wraparound vulnerability in academysoftwarefoundation openexr. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 18-06-2026
   PublishedVulnerability first disclosed.
2. 22-06-2026
   Last modifiedVulnerability information updated.

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.

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.