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CVE-2026-34380

CVE-2026-34380 · OpenEXR has a signed integer overflow (undefined behavior) in undo_pxr24_impl may allow bounds-check bypass in PXR24 decompression

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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 undo_pxr24_impl() in src/lib/OpenEXRCore/internal_pxr24.c at line 377. The expression (uint64_t)(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.

CVSS 5.9 · Medium · EPSS 0.3% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • openexr

    Versions
    • >= 3.2.0, < 3.2.7: Affected
    • >= 3.3.0, < 3.3.9: Affected
    • >= 3.4.0, < 3.4.9: Affected

    No fix published

  • openexr Debian:12

    Versions
    • 3.1.13-1
    • 3.1.13-2
    • 3.1.5-5
    • 3.1.5-5.1
    • 3.1.5-5.1+hurd.1
    • 3.4.14-0.1
    • 3.4.15+ds-1
    • 3.4.16+ds-1
    • 3.4.6+ds-1
    • 3.4.6+ds-2
    • 3.4.6+ds-3
    • 3.4.6+ds-4
    • 3.5.2+ds-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • openexr Debian:13

    Versions
    • 3.1.13-2
    • 3.4.14-0.1
    • 3.4.15+ds-1
    • 3.4.16+ds-1
    • 3.4.6+ds-1
    • 3.4.6+ds-2
    • 3.4.6+ds-3
    • 3.4.6+ds-4
    • 3.5.2+ds-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • openexr Debian:14

    Versions
    • 3.1.13-2
    • 3.4.6+ds-1
    • 3.4.6+ds-2
    • 3.4.6+ds-3
    • 3.4.6+ds-4
    Affected ranges
    • ECOSYSTEM: < 3.4.14-0.1

    Update to 3.4.14-0.1

  • openexr Ubuntu:Pro:24.04:LTS

    Versions
    • 3.1.5-5.1
    • 3.1.5-5.1build1
    • 3.1.5-5.1build2
    • 3.1.5-5.1build3
    Affected ranges
    • ECOSYSTEM: < 3.1.5-5.1ubuntu0.1~esm1

    Update to 3.1.5-5.1ubuntu0.1~esm1

  • openexr Ubuntu:25.10

    Versions
    • 3.1.13-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • openexr Ubuntu:26.10

    Versions
    • 3.1.13-2build1
    • 3.4.6+ds-4ubuntu3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • openexr Ubuntu:Pro:26.04:LTS

    Versions
    • 3.1.13-2
    • 3.1.13-2build1
    Affected ranges
    • ECOSYSTEM: < 3.1.13-2ubuntu0.26.04.1~esm1

    Update to 3.1.13-2ubuntu0.26.04.1~esm1

Original sources

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