OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. In versions 3.3.0 through 3.3.6 and 3.4.0 through 3.4.4, a heap-buffer-overflow (OOB read) occurs in the istream_nonparallel_read function in ImfContextInit.cpp when parsing a malformed EXR file through a memory-mapped IStream. A signed integer subtraction produces a negative value that is implicitly converted to size_t, resulting in a massive length being passed to memcpy. Versions 3.3.7 and 3.4.5 contain a patch.
{
"sources": [
{
"url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-26981",
"database_specific": {
"status": "Analyzed"
},
"html_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26981",
"modified": "2026-02-25T17:30:34.797Z",
"id": "CVE-2026-26981",
"imported": "2026-04-17T13:59:24.446Z",
"published": "2026-02-24T03:16:01.890Z"
}
],
"license": "CC-BY-4.0"
}