CVE-2026-62986

OpenEXR is the reference implementation and specification for the EXR image file format, widely used in the motion picture industry. In versions 3.3.0 through 3.3.12 and 3.4.0 through 3.4.13, the PyOpenEXR Python bindings return stale heap data when reading a crafted deep scanline EXR that uses layer-prefixed RGB channels. With the default channel coalescing (separate_channels=False), the wrapper groups channels such as left.R, left.G, and left.B into a single RGB sample array, but the lane-offset calculation in PyPart::setDeepSliceData() only recognizes the exact unprefixed names G, B, and A. As a result, prefixed channels like left.G and left.B are decoded into lane 0 while lanes 1 and 2 are left uninitialized and returned to Python. A Python application that reads untrusted deep EXR files through the default OpenEXR.File API and then logs, serializes, previews, or otherwise processes the resulting NumPy sample arrays may expose uninitialized same-process heap contents, in addition to receiving incorrect green and blue channel data. This issue is fixed in versions 3.3.13 and 3.4.14.

Scoring

Severity
MEDIUM
CVSS base score
4.3
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
EPSS probability
0.23%
CWE
CWE-200, CWE-457, CWE-908
Published
2026-08-25
Last modified
2026-08-25

Affected products

Weakness type

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