UBUNTU-CVE-2026-34380

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 signed integer overflow exists in undopxr24impl() in src/lib/OpenEXRCore/internalpxr24.c at line 377. The expression (uint64t)(w * 3) computes w * 3 as a signed 32-bit integer before casting to uint64_t. When w is large, this multiplication constitutes undefined behavior under the C standard. On tested builds (clang/gcc without sanitizers), two's-complement wraparound commonly occurs, and for specific values of w the wrapped result is a small positive integer, which may allow the subsequent bounds check to pass incorrectly. If the check is bypassed, the decoding loop proceeds to write pixel data through dout, potentially extending far beyond the allocated output buffer. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.

References

Affected packages

Ubuntu:Pro:24.04:LTS / openexr

Package

Name: openexr
Purl: pkg:deb/ubuntu/openexr@3.1.5-5.1ubuntu0.1~esm1?arch=source&distro=esm-apps/noble

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

3.1.5-5.1ubuntu0.1~esm1

Affected versions

3.*

3.1.5-5.1

3.1.5-5.1build1

3.1.5-5.1build2

3.1.5-5.1build3

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "3.1.5-5.1ubuntu0.1~esm1",
            "binary_name": "libopenexr-3-1-30"
        },
        {
            "binary_version": "3.1.5-5.1ubuntu0.1~esm1",
            "binary_name": "openexr"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34380.json"

Ubuntu:25.10 / openexr

Package

Name: openexr
Purl: pkg:deb/ubuntu/openexr@3.1.13-2?arch=source&distro=questing

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

3.*

3.1.13-2

Ecosystem specific

{
    "binaries": [
        {
            "binary_version": "3.1.13-2",
            "binary_name": "libopenexr-3-1-30"
        },
        {
            "binary_version": "3.1.13-2",
            "binary_name": "openexr"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34380.json"

Ubuntu:Pro:26.04:LTS / openexr

Package

Name: openexr
Purl: pkg:deb/ubuntu/openexr@3.1.13-2ubuntu0.26.04.1~esm1?arch=source&distro=esm-apps/resolute

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

3.1.13-2ubuntu0.26.04.1~esm1

Affected versions

3.*

3.1.13-2

3.1.13-2build1

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "3.1.13-2ubuntu0.26.04.1~esm1",
            "binary_name": "libopenexr-3-1-30"
        },
        {
            "binary_version": "3.1.13-2ubuntu0.26.04.1~esm1",
            "binary_name": "openexr"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34380.json"