openexr — security advisory
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Products
- openexr
- Affected versions
- 3.1.13-2build1, 3.4.6+ds-4ubuntu3
- Fixed versions
- Not specified
- CVEs
- CVE-2026-34378
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:00 UTC · Revision 1
Source evidence
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
osv:UBUNTU-CVE-2026-34378
openexr
Fixed versions: Not specified
Complete source record
{
"id": "116815c3d093d9185b5def9398e13c5166789059c5b3eab15beaf2d066086ce2",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-34378",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-34378",
"summary": "OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.",
"evidence": "osv:UBUNTU-CVE-2026-34378",
"products": [
{
"name": {
"value": "openexr",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.1.13-2build1",
"evidence": "/affected/0/versions"
},
{
"value": "3.4.6+ds-4ubuntu3",
"evidence": "/affected/0/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-34378",
"aliases": [
"UBUNTU-CVE-2026-34378"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "openexr",
"purl": "pkg:deb/ubuntu/openexr?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"3.1.13-2build1",
"3.4.6+ds-4ubuntu3"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34378.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libopenexr-3-4-33",
"binary_version": "3.4.6+ds-4ubuntu3"
},
{
"binary_name": "openexr",
"binary_version": "3.4.6+ds-4ubuntu3"
}
]
}
}
],
"modified": "2026-10-17T13:00:01.050597326Z",
"provider": "osv",
"upstream": [
"CVE-2026-34378"
],
"references": [
"https://ubuntu.com/security/CVE-2026-34378",
"https://www.cve.org/CVERecord?id=CVE-2026-34378",
"https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-v76p-4qvv-vh4g",
"https://github.com/AcademySoftwareFoundation/openexr/pull/2321",
"https://github.com/AcademySoftwareFoundation/openexr/commit/088859fb6199e56824c4c9ed60afc825261bfea9",
"https://github.com/AcademySoftwareFoundation/openexr/commit/7a1c64ca74d12bf5f64a912d4e12a651689f8652",
"https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.9"
]
},
"related_cves": [
{
"value": "CVE-2026-34378",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360130,
"published_at": "2026-04-06T16:16:00+00:00"
}